I used to check player ratings updates on https://2700chess.com/rapid which is usually promptly updated, often within few minutes from the match end (at least during the last FIDE world cup this was the case).
I noticed though that during and after the last Aimchess Rapid 2021 tournament no elo changes of sort have been recorded. Is it just because the maintainers did not update it or is it something with the tournament? Or what?
FIDE operated tournaments are more likely to process the data and results more promptly as it doesn't require a significant amount of correspondence. I have played FIDE tournaments and had updates reflected within hours, I have played FIDE tournaments and the results weren't updated till about 24 hours after the last game. National tournaments that have take weeks to reflect. Its all about how promptly they are processing the data , getting it into the FIDE system.
More likely though the AimChess tournament is an online tournament. Refering to the FIDE handbook, the rules only cover traditional chess and exclude Correspondence and Online chess(https://handbook.fide.com/chapter/E012018). So there probably are no rating changes as a result of that.
