I have visited shops to find them full of Magic and other TCG players, but no role-players
I have posted on relevant socials and Discords like the Discord server for a game store, local area RPG players Discord and FB pages, LFG groups on reddit and Lemmy and Discord
If you've done all that and you're still not getting any bites as a GM looking for players, I'm inclined to think there is something wrong with your pitch that is turning people off. Usually GMs looking for players have the problem of too many players being interested. Maybe it's because you're looking for pen and paper players as opposed to an online group? Are there any unusual requirements you've put forth in your posts on these communities?
Some people might be a bit nervous about playing in-person with a totally new group. Perhaps you could offer playing online virtually with people in your local area first, and then if you all vibe, you could meet in-person after that.