Do you think too many meetings decrease productivity?

I think so. Instead increasing short conversation among coworkers is beneficial.

Yes Every time you create a meeting, there should be a Google Calendar integration pop-up that says: - "Are you sure that can't be a long slack message or email?" - "FYI, given the monthly salary of the people invited, this 2hour meeting cost $12,000" - "Are you really really sure you want to proceed?"

Definitely, we are fully remote team at Gossip with people in Russia, US and EU - we try to stick to 3 meetings per week and do the rest async or 1-1 calls if needed.

Our meetings usually last 30 minutes with 12 people. Too many meetings with long hours are not effective. A person usually can only remember 3 things after meeting in my opinion

sometimes sitting on a meeting I think (why am I here?)

Definitely, because of context-switching and cognitive load required. That's why I theme my days and have meetings day, deep-work days etc.