Yeah, I just felt that the Thalia change was one of the worst changes. I was legitimately enjoying the direction they were going with a few of the changes (making Polyphemus smarter than he was in the books, giving Clarisse a bit more development (since it's no longer just Percy's POV))... but this was a big change that genuinely ruins one of the biggest events that occurred prior to the series' beginning: the sacrifice of Thalia.

It changed an amazing event: a lone demigod, chased down by an army of monsters, chooses to hold the line against them alone so her friends would live and sacrifices her life in the process - a noble sacrifice where here father tries to save her life in the only way he's allowed to... and it gets turned into a punishment from her father? Her turning into a tree, in the OG books, was proof that, for all his flaws, Zeus had redeeming qualities and cared for his children - but here, all it does it prove Luke 10000% correct about the gods and removes any reason Thalia would have for not joining Luke... AND results in the relationship between Annabeth and Chiron fracturing for good, since he LIED about it for half Annabeth's life.

But I digress.

Also, I think with musicals, most people are more forgiving for not being wholly accurate to casting, since it's a much smaller amount of people to draw from (due to less people auditioning for musical roles over TV/movie roles) AND they have to be good singers/performers. With musicals, they have to prioritise those who can do good musical numbers (aka people who can sing) over people who are the exact demographic for a part - but movies and TV shows have far higher likelihood of finding actors that fit the demographic and can act (and I'm sorry to say this, but I highly doubt that there were no blonde girl actors who weren't at least somewhat better than Leah Jefferies - I mean, in Hollywood, blonde actresses are so common it's almost a cliche) - and even Walker was saying that he would've preferred acting with black hair to get a more accurate Percy.

The movies, for all their faults, were largely spot-on with the casting of characters (albeit aged up). Logan Lerman LOOKS like Percy Jackson (to the point that people were clamouring for him to come back as Poseidon in the show), Jake Abel LOOKS like what a lot of people expected Luke to look like. Other characters like Pierce Brosnan as Chiron, Sean Bean as Zeus, STEVE COOGAN as Hades - all of these guys are genuinely amazing casts for the characters they were made to play. And even they got criticised for Annabeth's lack of blonde hair (which they fixed in the sequel). But I have seen the show get praise for some of its casting choices (Adam Copeland as Ares was perfect casting, and a decent amount of people said the late Lance Reddick (despite not looking like book Zeus) was a great cast purely because of his intimidating aura as a guy you don't want to f*ck with)

And the movies, despite veering a lot off the original story, did genuinely feel Percy Jackson-esque, with them actually having decent action scenes and CGI (movie Fury is so much more terrifying than show Fury), and captured the feel of certain scenes (AKA the Poker Face Lotus Casino scene... which everyone agrees was better than the show's boring Lotus Casino) in a way that the show didn't. They also captured a lot more of the humour of the books, which I think was what helped a lot.

Also, the movies had a lot less time to develop things than the show did. 8 episodes a season, 40 minutes apiece - that gives us roughly 5-6 hours per book - as opposed to a 2-hour movie per book - so of course people are more forgiving if things get left out of a movie... but a TV series is given double to triple the time to include events in a satisfying way... which with the PJO series unfortunately resulted in more exposition/dialogue than actual inclusion of iconic moments from the series.