[Question] Why not more small, intense research teams?

Why are we not fostering more teams of say 2-5 people that

a) work full-time on the same or closely related problems

b) live together or very close

c) spend most of their work time collaborating in-person


I’m aware of student groups etc. but these fail both a) and c).

Plausibly this has advantages over both individuals (more perspectives, motivation, etc.) and larger orgs (tighter feedback loops and communication, more flexibility, much easier to hire, etc.).