I can chat with someone for hours on end, but I also like using my own toilet, and having access to a tea, snack, etc.
For me, what blocks having random conversations is having 1-3 hours of status updates daily - it doesn't leave much leftover to do the work especially when my firm declaration that it was going to take twice as long as someone else estimated (and then sure enough it did, at minimum, and maybe taking 10x) is ignored. That would block conversations regardless?
Anyway, the conversations are the content, but them being present physically is only the medium, so WFH does not need to block them, and if anything can help facilitate them e.g. working one in-between other meetings whereas the time taken to physically walk over would have been prohibitive.