Since we're talking about players and DM's, can I ask some advice? Where can I go to find players for my own campaign? I am a boomer that has been out of the gaming loop for a long time and haven't been able to find a group in my time zone. So I've been kicking around a fun concept to DM myself. Sort of a CoCthulhu lite meets Stranger Things (never watched the show). Sort of a monster of the week with an overarching plot, like X-files but set in a university in 1985. I have some homebrew ideas, but not sure what system would work best (nothing too lethal, so no CoC)
One option is Reddit l4g, roll20, etc. Heaps and heaps of trash and trash hidden behind a disguise and lots of disappointment awaits. But surely there's someone out there. It's the easiest in terms of masses of people seeing your advert, but you'd probably get filtered out with such a vague idea and no system in hand.
Another option is to look at communities you're already a part of (like here), ideally with similar interests, and trying to get interest there. You probably share at least something with those. You'll still need to come up with a more concrete concept and idea if people are familiar with TTRPGs or RPGs at all - ruleset is important, especially among gnognards.
I think
mediocrepoet's idea is valid, but only in certain countries. We don't have gaming stores here anymore, for example. And I imagine you end up not being able to filter out stupid people and end up with idiots that you then have to kick out, which can create drama. I wouldn't recommend it myself, but I also have no experience with it.
My ideal way was finding people local to my area (via youtube, people who watch D&D streamers. small communities, just dozens or hundreds viewers at most, and their communities) and introducing them to my particular flavor of TTRPGs slowly. I got to know them first, then invited the people I meshed with in for a game. It worked out. Again, you have to have a concept in time and there is a time investment in getting to know those people, at least virtually.
Finally, there's introducing new people to the game. The good news is, you can get away with little preparation, those people rarely know any better. The bad thing is, you'll again get people who are simply not suitable for the game with a difficult task of filtering them out. It depends on how well you know each other and how honest you can be.