There is IMO well-justified use cases for in-person collaboration. As much as technology has reduced the effects of distance, the penalty is non-zero for some things. It's unfortunately still a lot easier to do some things remotely.
The trick IMO is that there's a big gap between "sometimes we feel the need to be in-person" and "we should be in-person all the time/most of the time". I think the latter statement is incredibly poorly substantiated.
The answer to all of the above is pretty straightforward: scheduled, reserved in-person time where the entire team meets. You kind of have to do this anyway! If you have developers in New York and Chicago and San Francisco and Tokyo who are all in-office, you still need to do meetups!
Have a travel budget, set up in-person sprints on a cadence that works for your team!
If the world has been mostly remote well before the pandemic, what does this say about the idea that outstanding results can only be produced by the serendipity and (alleged) increased efficiency of in-person collaboration?