The IMDB audience rating, while still a non-scientific self-selecting pool, is a tad bit more of a reliable indicator. One reason is that despite RT getting all the press, the IMDB poll can often get ten times the number of people rating the movie. It's not uncommon for IMDB to have the number of ratings in the hundreds of thousands, and sometimes, millions. So, while self-selecting, it does provide a much larger pool that softens the clout of the extremists.
And because RT gets most of the press, when people want to bomb a movie, they tend to focus there rather than IMDB for the public impact of their bombing. And with less user ratings, it's easier for the bombers to move the needle there.
And finally, the IMDB user ratings are usually in line with the CinemaScore, which is a scientifically sampled pool.
The CinemaScore and PostTrack scores for Aladdin are very good. The RT and IMDB scores are in line with that. When they're not, that's when either because the opening night audience was wildly disrepresentative of the general movie-going population, or, the audience ratings were bombed (as was the case for certain other recent Disney properties whose names I shan't mention lest it summon their Ahab and make it the topic of yet another thread).