I actually don't like Styles as a mechanical solution. I agree that they work and are well implemented, but as far as what they are, they don't appeal to me. They're a very good teaching tool for a wide audience, but I actually enjoy a larger, more granular approach to things.
Like, this is firmly my opinion as Shyft, in how I run my own games or the games I would prefer to play, but I like making full 2e-style Martial Arts Styles. I've gotten good at that. I'm comfortable at it and I tend to associate with people who are comfortable with that. I do agree that MA as presented has systemic problems, but I'd rather solve them a way more preferable to my tastes.
Styles cater instead to the people who don't like that, who believe (not wrongly) in spending their creative effort elsewhere. It reduces ST and player overhead, sure, which are positive traits, and has numerous second order benefits... but it's unsatisfying to me as a player.
I can understand that point of view, but at the same time you don't end up with half a dozen martial arts trees that are different only in where they place certain types of Charm and some minor cost differences.
Sure, a Martial Art is a good way to distinguish your character, but if your campaign grows enough in experience you run into the problem that Martial Arts are closed trees, can't keep up with native Charms and that most are really similar in what they allow you to do with your magic. Styles though do allow you to expand into a new field of competence without running into a massive experience sink due to duplicate Charms.