Run less or no meetings. If you have to run meetings, consider the option to temporarily institute an approval process by senior management whereby the thesis for any meeting (proposed agenda, attendees, etc.) is first proposed in private. Then senior management has the opportunity to ask questions and give feedback. This alone will force those convening to think twice. If necessary, quantify the cost of the meeting…
On the specifics of the meetings I've implemented 2 things:
1) Offer no-video meetings, maybe for 1:1 if you don't need to screen share. Be the first to go on a walk or be away from keyboard, to encourage others (especially new team members) to do it as well. Clearly I'm not sayin ALL 1:1, face time also has value, use your judgement.
2) Include a bit of non-working life. The way we were running our weekly sync was talk quickly about what you did/didn't last week (especially to catch blockers), share what's your plan for this coming week, share something you did during the weekend. 8-10 people, 30min.