I'm a manager of a team of 8. I've set a rule that you are free to skip or escape any meeting. We even use the nickname "the 2 feet rule : if your time is better spent someplace else use your 2 feet and leave.
I rarely see someone skip a meeting, and exceptionally seen someone leave one ; and almost every time they justify why. This is despite renewing the statement almost every meeting. And the meetings I'm in, despite having value most of the time, are NOT perfect in any regards, NOT useful or enjoyable to everyone, and do not require everyone in.
I'm regularly sending anonymous surveys on topics. One had questions around meetings, cadences and masses. About half the team doesn't mind the meetings and saw value in them, the other figures we have too many. The reasons why people are not leaving were majorly 1. peer pressure and fear of looking bad and 2. FOMO. And I consistently get good reviews as a manager...
I'm balancing between limiting the attendance (but ego / disappointment of not being invited?), reversing the default (why are you here?) or simply cancelling/forbidding them and trying to replace by other media (online collaboration?).
But the fact is that in a team with a lax manager on the topic who keeps repeating "not mandatory, get out if you want, no hard feelings", peer pressure is enough to keep people in.