I've seen a lot of DJs post links on subreddits like /r/mixes to their 2-3 hour sets on Youtube. Why? I listen to DJ sets while doing active things like going for a walk, making breakfast, doing chores etc and I can't listen to anything on Youtube without having the app open because I don't have Youtube premium, plus I would imagine Youtube commercials will pop up often in a long set.

I don't get it, why not just post your mix on Soundcloud or Mixcloud instead?