Any point taking the bonus training for the extra skills?

[Ciaran Zagami]

Why bother unlocking the hidden moves for each style when the Legend Styles exist and are the best (save for the fact you can't use ANY of the skills from the other styles)

[ReissyBoi]

Majima's Legend style isn't even that good. The only good thing about it is defeating 3 enemies instantly at the start of a fight (Heat Move) and his counter attack. Breaker ♥♥♥♥♥ all over groups of enemies, and being able to stunlock enemies with Slugger is just much better

Kiryu's Legend style is a much better version of Brawler, but you don't have the speed of Rush and the tankiness/weapon handling of Beast, both of these are needed at some point during a fight

Also certain skills from each fighting style gets unlocked for Legend too, so there's an incentive to unlock them

[Bstel]

Because the Legend Styles aren't that great? Mad Dog of Shimano is good for crowd control, but not as good as Breaker, or Slugger's bat nunchaku move which breaks down enemies' guards. Majima's Legend Style is the exact same fighting style he uses when you fight him as a boss throughout the older games, and it's more for nostalgia points.

Kiryu's Legend style is literally his fighting style in Yakuza 1-5 with a few changes. It's a refined version of Brawler, but with less heat actions (like Brawler's heat action after you get knocked down). Its counters are also much more frame-sensitive than say, the counters of Brawler's or the counters of Rush. DoD is an all-around good style, similar to Brawler, but changing fighting styles is just much more fun instead of sticking to one. You're literally untouchable with the Rush fighting style if you know what you're doing.

And like what Reissy said, some skills from the other styles transfer over to the Legend styles after you unlock them.