@Johnny:
Honestly, yeah, DBZ really is pretty awful. I mean, there's always the nostalgia factor, and the turn off your brain coolness, but most of it really is crap writing.
No, its still a well paced action battle series with likeable characters and cool moments and some of the best fight choreography manga has ever done. It hold up, its still great.
The problem is you've seen a lot of it now.
At this point you've seen others trying to follow up a story that was done twenty-five years ago, and they haven't really brought anything fresh to the table. And the lesser talents just repeating those same beats over and over dilutes things and wears them out, and makes them less fresh.
Super 3 and fusions were about the upper limit for transformations that being cool, and even Toriyama knew it had been played out even then, which is why he made such a joke out of the kids being able to go super siayan so easily, had fusions not win the day, and eventually even made the announcement with Gohan that "yeah, these are played out Base form now."
But once you added 4, red, blue, kaioken blue, blue blue, neutral for Gohan, white… yeah of course it gets old. God form red aura by itself should have carried through most if not all of super, with maybe pulling out ultra instinct at the very end.
The anime and manga follow ups since then have... repeated Frieza. Multiple times. And repeated Broly. And done a really overlong tournament. The only new thing they really tried was Zamasu, and even that got super muddied with time travel and multiple bodies and Goku Black. Jiren was a complete joke for lacking personality that no one is going to care about or remember, and goat boy is basically just reprising what Maijin Buu and Cell did and the story beats and twists are playing out IDENTICALLY. Not offering anything new.
Beerus was just about the only breath of fresh air because he had actual Toriyama spark and is a silly villain rather than a serious monster. That's why he was so fun and fresh... until they beat him into the ground and overused him.
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Original dragonball had the adult Goku Z adventures last for a little over six years of real time. A little over 300 chapters. And that was about the right amount of time for them. All the extensions since, especially since the series demands Goku and Vegeta do everything, and that every villain have multiple forms, of course it becomes rote and old and starts to make the original feel janky... because its taking everything good from it and stretching it thin.
And even outside of Dragonball itself wearing it thin, every shonen battle manga to come along since has been inspired by and steals from it, One Piece and Naruto being the obvious big sequels, but basically every fight series owes it a debt and has worked to grow the formula or change it in some way, so Dragonball shows its age a little that way, and that's no fault of its own, any more than there a thousand cartoons that ripped off Star Wars..