That watercooler talk getting lost is absolutely a pain point with remote work, but there are mitigations and benefits that offset it in my opinion.

One option is to re-create that talk. At a past job we would often all fuck around before/after standup calls for a bit, but sometimes that fucking around became work and solved problems. Other times we would just call each other either one-on-one or in small groups just to shoot the shit, and that can recreate that same feeling.

A big part of that is getting over the idea that "calls" are somehow different than walking over to someone's desk, you wouldn't hesitate most of the time to walk over to a coworker and start chatting, but most people hesitate to call someone on slack. At a past job that hesitation wasn't there because the culture embraced it, and suddenly we had our watercooler talk back, just over video calls.