This is exactly why everyone I know who went to film school ignores rhe IMDB ratings system. They all use it for posting their projects and cast info, but even that sucks because they make the format of the website worse every six months or so.
The longer I live, the more I'm convinced that there's no reason for creators to look at any kind of ratings score. At most, just find some critics/other people whose opinions you trust and follow them.
Numerical scores suck for creative works in general because there's no real sense of calibration and "this is middle of the road mediocre" can easily net the same score as "this is written amazingly but the sets are made of cardboard and the steadicam was broken."
Sure, but things like Rotten Tomatoes have some utility. You can compare the critical consensus versus monetary success of a film. For big blockbuster films, something critics I like don't cover a lot, I can skim over the aggregated reviews and see if the film is something I'd like to see or not. I can also point to the red tomato and convince my friends, no it looks dumb or gloomy but lots of folks enjoyed it etc.
I agree numbers don't accurately represent a subjective art form, but they are helpful for navigating a huge growing library of media that we have access to. The problem is that IMDB is run and populated by absolute gits.