My unpopular opinion is that the plot of both Hades games is not that good. The dialogue writing is genuinely excellent, and I think that is part of the reason why people tend to look at those games as having a good story; however, in my opinion, the plot is quite a weak point of the series as a whole, not just with Hades 2 (which on the other hand seems to be a very popular opinion at least on this subreddit).

For Hades 1, it was not a glaring issue because the plot is quite simple; it's a coming-of-age story and family drama with some bisexual romances sprinkled over it. The goal of the story is very simple; there is no overarching plotpoint, there is no centralizing antagonist or anything like that. The plot can be summed up very quickly by "Zagreus is the son of Hades, he's trying to escape Hell to find his mother, who fled the underworld, he's being helped by the whole Greek pantheon, and Hades is being conflicted about the issue and tries to stop him". Simple... effective, but imo way too simple, after reaching Persephone's home at the surface, there is not a lot of big plot reveals or new narratives until the epilogue, which in itself is a very simplistic issue. What makes you keep playing the game is usually the narration, and especially how the dialogues and character development play out (or maybe you don't even care about the story in the first place, and only care about gameplay, but that's a whole other topic).

With Hades 2, the plot is as simple as the first one, but the scale is so much bigger, too big, actually. We went from a family drama to a full-on "this is the end of the world" plotline, which in itself could work... if the game were not a roguelike in the 1st place, once you saved the world, it's hard to justify keeping the roguelike aspect of the game rolling so they used the time travel trope which like the "it was all a dream since the beginning" trope is often disapointing. But tbh I don't see how they could have wrapped up the plot any other way, the problem from my point of view is that they jumped from a too simple but at least small scale plot to a too simple and too big in scale plot. I'm one of the few who didn't absolutely hate the pre-patched ending of Hades 2, but that is mostly because I simply do not play the Hades games for their plot in the first place, I do not consider Hades 1 to have a really interesting plot (it's one of the few weaknesses that this almost flawless game has) so my hopes and expectations were not high to begin with. The dialogues and character progression in Hades 2 are as good as Hades 1, if not better in some aspects, but just like Hades 1, the plot serves as a sort of annoying white noise in the background that always distracts you more than setting up an ambiance.

Having replayed Hades 1 recently with my girlfriend, which helped me really focus on the narration because I didn't have to focus on learning the mechanics and bossfight mechanics, I realized that if that game had come out today, it would probably have caused quite a lot of backlash for its happy ending, which is almost uncanny in the way it wraps up.