I don't think I've ever personally witnessed a large friend group that doesn't rely on some form of hierarchy and groupthink. I'm sure there are healthy friend groups out there, but more often than not they seem to turn into a vehicle for subtle or just plain obvious harm.
Groupthink will always be creepy to me. I can't stand the cruelty it produces. I sense it quickly from painful past experiences. There always seems to be some sort of sacrificial lamb in each group just as there's a leader that everyone is too scared to push back against.
The system plays out the same way every time like some sort of copy paste coding in the human mind. I've seen it happen too many times at this point that I have to flag them as a risk.
I think it seems like a better idea to have individual friends. It keeps things pure.