I think in order to answer the question, it might be more important to characterize the size, maturity and existing organizational structure of the medical device company. Medical devices are made with a widely different types of organizations. Some a very small (less than 100) such as a small clinical organization to very large (>50,000) such as Becton Dickinson. Also need to understand the structure of the organization. Large organizations typically create a functional grouping such as engineering, production, marketing with clearer boundaries. Smaller organizations may require you to wear multiple hats. Also need to understand a number of projects in the organization, their product lifecycle and mature their organization is to project managers and functional managers working with the resources.

My experience with larger firms would suggest functional or possibly matrix is there is a PMO created to manage projects on a full time basis. Aa a consultant now, I see smaller organizations wanting to get more formal but struggle transitioning to a project management driven organizations. Each functional group as mentioned in the lecture prioritize their work and do not sense the need for project management coordination roles. The functional managers seem to discuss between them and feel they are the "project managers."  It could work sometimes but often it does not. Not enough time working the project as opposed to other duties that their roles need. 

Personally I seem to like the idea of a Project Based Organization structure. To answer your question on which type of medical device company would benefit the most from this, I would imagine one which mainly focuses on R&D would do best here. Additionally it should be noted that the company would also most likely be a small one and which does not have that many employees. The benefit to this structure is that one one project is done, you are already familiar with your co-workers strengths and weaknesses, and as you move forward your team will only become more efficient and productive as time goes on, theoretically speaking. 

For a larger company this structure may not work as well since there may be several different projects occurring simultaneously, some at different paces than others. Therefore it would advantageous to implement a matrix organization based structure.

Personally, I work in the pharmaceuticals and I believe we see a lot more of the matrix solution being used combined with a type of functional  organization. For me, I directly report to one functional manager who manages my personal growth and day to day operations. And the first half of my day is dedicated to that task in hand, however, afterwards, I have my other projects that I have which have their own project managers who over look the projects. So in total, the function of having a highly diversified organization type i believe makes for a better and more robust company depending on the company size and complexity. Working for a large pharmaceutical company comes with its own set of challenges which are met by using unconventional tactics such as this one type of organization type. 

However in the medical device sector, I believe that a matrix situation would be the best course of action strictly because it allows for one resource to be used more tactfully and with better efficiency for the company overall.

In the last two years, I have noticed a shift in medical device companies organizational structure and a push from my company's management to transition to a matrix organization with a project management office (PMO). This is because a PMO is better structured for assessing risks and generating a stronger R&D pipeline. You can checkout more in this blog detailing why medical device companies are transitioning to PMO, especially post pandemic: https://www.planisware.com/hub/blog/2020-marked-new-turn-medical-device-industry  

In terms of work organization I think that the pharmaceutical industry specifically the drug discovery and development sector could largely benefit from using the Matrix Organization as there are several departments that are existing and operating simultaneously. In drug development there needs to be a team that is searching for the potential molecules that can be used as a therapeutic, theres a department involved in conducting in vitro testing, a department that is responsible for actually manufacturing the drug (just to name a few). These separate departments function individually in terms of their results, however, the results from each department come together to eventually lead to the final product that is produced and sent to market to be sold. With the Matrix organization each dept can be spearheaded by a Project Manager that can effectively make sure that the dept is accomplishing what needs to be done. In this structure there is a good management of resources and open knowledge is shared amongst departments which is crucial for this industry where each department has an effect in the long run on each other as departments. A functional organization method would not be effective in this scenario as this type of construct tends to promote exclusivity amongst the departments and there is a communication disconnect. Additionally decisions also tend be made by one person which is not wise or effective in drug development as there are several working factors that need to be accounted for that one person cannot make a decision on. 

Like @ag2265 stated, the Matrix Organization is highly beneficial when done properly in an organization maintaining day to day tasks and simultaneously executing projects. I saw a major disconnect between the project teams and operations teams when I worked in a Chemical Plant before. This lead to plenty of rework and inefficiency. You need strong functional and project managers in this role, however, as managers with a narrow mindset (improving just their metrics or competing internally) will minimize any collaboration between the teams.

I believe public schools work within a functional organizational structure because there is HR, one principal, maybe one or two asst principals, admin, then admin support, school support (nurse, custodian, aides) and then there are teachers. They all typically work in their own role and very rarely go into another role. Everyone is responsible for their own actions and at the end of the day, they report to the main person in charge which is the principal. I believe this system works best within a school system because everyone knows their strong suit and abilities I hate to sound demeaning but know their place and hopefully don't overstep their boundaries and hopefully the lines aren't blurred. Yes, they all work together to have a functional atmosphere and do correspond throughout the day and during meetings, etc, but there is also a chain of command that must be adhered to.

I think in regards to the medical device industry, it can very well vary based on the device, company, etc on what best suits the company as far as the organizational structure. For some companies it may work best for them to be functional if they are working on a specific device, then for others, if they are working on multiple devices may be the project-based structure works best and people can come up with their own thoughts and ideas and put them into action, etc.