I notice you are using a nineteen point rating scale, going from 1 to 10 with halves in between and a slider. You will get better ratings if you use a more standard scale that's compatible with other sites and a better method for inputting ratings.

You'll want to link your rating data to other sites (eg, backloggd.com, igdb.com) if you have any hope of this being used, so that's why compatibility is valuable. Mapping a 10 point scale to a 19 point scale is a silly wrench to throw in, and how will you translate your users' 19 point scale to push to sites with 10? You need to be able to keep users from entering scores over again to survive at all.

As to entry, something almost everything gets wrong is you actually get better data if you present ratings with the right number of points to the scale and use a tiered grouping (visually, not as in requiring a series of questions for a single rating). There's basically a right answer here, and its 10 points grouped 3-4-3. The grouping helps cognitively because you're basically picking high-mid-low twice instead of analyzing a 10 point spread. People are significantly statistically worse at using a wide, flat rating scale, and the two-tier version corrects that and gives you richer and more accurate data, especially if you label the tiers, to help reduce individual bias about how they apply their feelings to numbers (eg the modern 6/10=bad syndrome).

We need better rating analyzers than we have, but it will never work without connecting to other rating systems and processing games outside itch.io. And if you keep your recommendation mechanism under wraps with only manual rating entries, especially limited to itch.io games, you're asking far too much from someone to see if it's potentially relevant to them, both in the sense of effort and the sense of trust ("non-biased, community driven").