Personally speaking, the big split is if I actually have to collaborate with someone or not. If I just need to focus on writing code, wfh is great. But if i actually need to design something, use a whiteboard, and have a conversation, it's a million times easier in the office.

This is why I think productivity went up in the short term, companies had plenty of stuff in their backlogs already and WFH let it get done faster. Give it a few years though and I'm expecting product and feature quality to start going down.