I never actually participated in discussions on there, but r/soccer is still my go-to source for keeping up to date with football news. That's probably the one I feel the most.
!football@lemm.ee seems to be the currently active football/soccer community on lemmy. Additionally there are club-specific communities hosted on fanaticus.social
I was on r/soccer a lot as well, and considering its size I don't know why the football communities are relatively small. Also, the .world one is effectively locked for some reason.
The main community was moved from .world to !football@lemm.ee in an effort to decentralise and spread communities out instead of consolidating on .world. It's somewhat active as smaller communities go on Lemmy, but nothing like the news hub you could use r/soccer for.