It's pretty much the question. You make a game, you can't reach your audience unless Steam publishes your game. You can upload and promo your game on social media but big players has already sucked most traffics, unless you pay them, but you can't pay them enough because big players pay 1000 times more than you. If you run your game with just 100-200 players they will leave soon cause people don't want to play with bots.