As said above, devs know what they’re getting into when they make a game and most often don’t expect revenue from it. But yeah, we’d be happy with people playing and sharing them. Good to rate, give reviews and spread the word.
But actually, if you do want to put a little more in, perhaps according to cynical metrics, post on Reddit about games you like. Badger YouTubers, commenting on games they should play. Sometimes it’s taken by them in a different way than a developer asking a YouTuber if they’re interested in playing their game. YouTubers may often be doing it for the views and won’t play a game unless there is demand for it. And smaller devs get more exposure if those YouTuber’s audience grows as well, so supporting them is supporting devs slightly.(YouTuber/streamer letsplays, video essayists, top ten lists.) like and reply to comments you see praising games you like and amplify them. It’s derisory but it all contributes to a little wind in the sails on the digital profile etc.