Hi. Your mistake, and the one that many people make, is thinking that Itch generates a lot of visibility. Itch is a terrific place for developers, but it doesn't have as much player movement VS the number of developers and games that are published every day.
If your game is good and you make updates, little by little you will build an audience, but this is a slow process and a few months is not enough time to generate a large community, especially if you have not promoted yourself in any other way.
If you want your game to have more reach, you must advertise it and not only within Itch, if not, go out and find your target audience.
Paying for advertising is not a bad option, but you have to do it smartly, otherwise you will be burning money.
There are games that have been programmed by people who have been programming for years and have built a community on various social networks, so you cannot compare yourself with them.