This is a good discussion topic related to the organizational structure. According to PMBOK, organizational structure is defined as an enterprise environmental factor which affects the availability of resources and influences how the projects are conducted.
As discussed by Dr. Simon that there is the disadvantage that there is limited knowledge sharing between project teams but according to PMBOK, some organizations came up with the solution for this: Composite Organizational Structure. In this, all the structure mentioned above are involved at various levels. With the involvement of all levels there is the inclusion of every department, and also it includes advantages for all the structures.
In my opinion, this structure is the best-suited one for the organization to run. Is there any disadvantage to this structure? And why it is not the most favorable structure for the different organization.