As a manager, I encourage my team to just say "no" where ever possible. I also always push to halve the times of meetings I'm in (and typically that works well).

- We have 10 min standup every day

- We have 30 min sprint planning every week

- We have 30 min retro every week

Beyond that we will talk as necessary between people. In reality pushing back is pretty effective at determining if a meeting is important. If they don't move it for you, you didn't need to be there.