Of all of the Dragon Ball movies this one does by far the best job of adapting elements of the TV show into a new version of the story and is the best at capturing the feeling of the TV show, but does so without feeling too beholden to it. It is also the first movie and one of the few across Dragon Ball, Z, GT, and Super, to introduce darker and more emotional moments and themes which I think is a great descion and really helps make Mystical Adventure feel like a more fleshed out experience rather than just some light-hearted fun. That's not to saythe movie doesn't have those aspects, it is still very fun and for the most part light-hearted, but with just enough darker moments to feel like there are genuine stakes, which is something sorely lacking in the previous 2 Dragon Ball movies and most of the 26 movies and specials in the overall Ball/Z/GT/Super franchise.

Mystical Adventure also really benefits from the fact that the Red Ribbon Army arc it's pulling a lot of elements from is far too drawn out and has a lot of weak parts in its TV show form, so setting it in an alternate universe/timeline and distilling the arc to 45 minutes of its best moments works really well.

This is still going to mostly be for people who are already fans of the series, but if you have some basic knowledge of the franchise and what dragon balls do I think you'd be able to understand and enjoy the movie enough that I'd still say it's worth giving it a chance.