Hi! I ran into this issue when I started speedrunning and wanted to help others. just post in this fourm and ask telling me you favorite games. feel free to help other to. :)
You could speedrun a Street Fighter II ROM Hack I made and moderate for, it’s really easy.
The super Dodge ball community is easy and with practice you can get good I’m a moderator of one of the games
A problem lies in convincing anyone to run our games, even for games that require the absolute bare minimum to win.
Getting more leaderboard entries isn't easy, indeed. It really depends on whether the game is popular or not. If it's a niche game, you're going to have a hard time getting more people to play.
The problem is people don't come to the forums very often, and this is the Introductions Forum, so I don't know if it's the best place to post about it.
I for one think popular games make it hard to carve your own space in the community but niche games make it easier