The Prequels were *bad* movies (I enjoy them but the dialogue is terrible and there are many other things that just don't work) but they expanded the Star Wars universe incredibly. We saw the capital of the Galaxy!!! We saw how the Republic worked (and didn't), we saw the Jedi at its peak, we saw warfare in a scale never seen before, we saw worlds and aliens and different aesthetics and themes. They also gave us characters like Anakin, Padmé, Obi-Wan, even Ahsoka and Darth Maul if you kept up with the animated shows that enhanced them. Even if you think that the prequels are bad movies, they GAVE a lot
The Sequels on the other hand, TOOK AWAY things from the universe. They took away the character arcs of the heroes of the main trilogy. They returned to the old Rebels vs. Empire playbook, Jakku is Tatooine, the rebels have bases in forested planets, everything is the same. There were a couple original things but they were buried into the play it safe soft reboot crap. They even retreated their own plot points which weren't even that original to begin with.
This is why I think that the Sequels will be poorly considered in the future. Not all of new Star Wars, I think the Mandalorian, despite all, will have a good legacy, same with Andor and other things. But I think the more time goes on the less people will be willing to redeem the Sequels. And this is only from the lore perspective, the messy production and how they treated beloved actors and characters will only make their legacy worse.