Stuff like Tekken have fleshed out characters by giving them individual story modes as well as a tournament mode, whereas FighterZ has a fanfiction story mode and half-assed galaxy whatever modes we already saw in Raging Blast/2. I have no doubt that FighterZ has plenty of references to the series in character movesets, and that the movesets themselves are way more deep and intricate than the typical DBZ fighting game like Budokai or Sparking. I don't care enough about playing as Roshi or Jiren to pay for the DLCs, the DLCs aren't available in the story mode, and the story mode is really all the game has other than online. Maybe if the story mode, instead of three versions of a bad fanfiction, had story modes for each character (along with story modes for DLC characters) I might feel differently, but overall I don't like the game all that much. It just plays like the games you mentioned above, with DBZ models serving as skins. It's not bad by any means, and if I could have friends come over during this COVID faggotry I might enjoy it more than Kakarot because I could play with them and not sweaty fat nerds online who spend all day on the game, but eventually I got bored, and bored faster than with several other DBZ games.
The bare minimum is completing the story mode, because you don't normally consider a game complete until you've unlocked all the characters and can play it to its maximum (DLCs nonwithstanding, although I did purchase Vegetto Blue).
Maybe if I didn't know what DB was and just purchased it as another fighting game in my collection, I'd enjoy it more than any other DBZ game because the combat is admittedly fast-paced and smooth. But my incentive for playing DB games is to live out the experience of the anime and manga, just like with Pokemon or any other Japanese game franchise. Can't really give it more bonus points for a DBZ game when the story is shit and I'd need to delegate large chunks of my free time as an adult with responsibilities to get good at it to the extent that online mode can entertain me.