Biscuit is wrong. Don't be a Biscuit. (Also, don't eat a mouse for lunch.)
There is no "right" kind of game or "right" audience. Steam is global, & it's built to give ANY kind of game the opportunity to find ANY kind of audience, so don't chase trends. Instead:
1-Make a game you're excited about, and make it good!
2-Know the kind of player you are making it for so that you can start thinking about how to find those players build your audience early (more on this soon).