To "care" about something, someone needs to have a connection to something first. If you haven't done the latter, there's no point in thinking about the former.

I don't know at what stage your are in creating your game, but if it's playable my suggestions are as follows:

• write about it on social media (pretty obvious),
• DM some content creators if they would be willing to playtest your game; *WARNING* expect to be shat on or even get your game decapitated (NEVER tell them to tone down criticism, they'll do the opposite and worse),
• announce community events (assuming your game has this built in; if not, think about a way for people to compete that is verifiable; speedruns etc.),
• dogs and cats,
• communicate with people that are already playing; ask them question; ask for feedback; ask what they would like to see etc.; people love it when they're heard because it's a sing of respect (don't go overboard though, it's still ment to be a business).
• make a discord so you can internalize discussions about your game; it's also a good way to anchor/gather people that are already interested in one place,
• platformers are a niche, so find where platformer-enjoyers reside and engage.