I have some advice! Itch is also a social platform. Just play other peoples games and comment on them (without promoting your game) and then they might be like "oh i wonder what this guy has made" and check out your game. Who knows you might find new players.
Also, if you think your game is good enough for say, youtube, maybe email a youtuber. Also, definetly promote on discord (be sure to check first if the discord you are in has no rule against it.) Also most discord servers i'm in have self promotion channels. Just dont be spammy about it.
Also, other social media, tweet about your games on twitter etc.
Marketting is hard. But eventually you will gain some audience.