* If tomatometer & audience score are within 5% of each other, you can trust the ratings to give you a decent indiciation of movie quality.
* If tomatometer is more than 15%+ higher than audience score, it means it's an artsy fartsy movie that critics like and movies don't.
* If audience score is 15%+ higher than tomatometer, it's a fun movie even if it's not oscar worthy. (https://www.rottentomatoes.com/m/old_school is a perfect example)
I believe IMBD can help you identify the "most popular" movie. But it's up to you to decide if that's a good indicator for quality.
To give you an example, look at the top 10 songs in Spotify worldwide and tell me if those songs are the "best" songs the art form can provide.
After going deep on an art form, being music, painting, sculpting or film making, you start to develop a taste and an appetite for more complex expressions.
What would you prefer, votes of 10 people that have watched over 1000 films or votes of 1000 people that have watched 10 films?