Just to be clear - the section I'm interested in is the "More information" tab on game pages, which do in fact show a round number star score as opposed to an average.
As an example, this game https://laundrybear.itch.io/morticians-tale has a score of 4.6 but when you scroll down and click "More information", it is shown as 5 stars.
I don't love star rating scores but I do think they're better than Steam's recommended versus not recommended system because yes/no isn't granular enough.