Shannara was an adaptation of the second book in the original trilogy, so, you know, way to skip the actual introduction to the setting, that leaned really hard on something that was not much IN the original trilogy, that the world is a post-apocalyptic setting. AFAIK, Brooks might not have even decided on that when he was writing the first few books (I read the first trilogy and the sequel tetralogy), because if there were references, they were too subtle for teenage me to notice.

They pulled some of the WoT show's tricks, like emphasizing physical combat skills for the heroine and teasing bisexuality in straight book characters, too.

I just could not be bothered with season two, since it looked like it was just continuing the story that ended more or less where the book did, albeit without the huge military conflict between the elves and the demon invaders, so now what was the plot of season two going to be, since we were not jumping ahead to the children of the (surviving) protagonists?

I don't recall hating on it as much when I first saw it, because the standards of fantasy adaptation were pretty low at the time (I was not thrilled with Game of Thrones, either). I was less invested in Brooks' writing, so I didn't pick up on the butchery of characters, setting and themes as easily as I did in viewing WoT, GoT and RoT (I mean RoP, or more precisely, LotR:RoP, though ROT is more accurately descriptive). I'd rank Shannara below Legends of the Seeker, which, after House of the Dragon, is the best we've got for fantasy series adapted for the small screen. Production values and stuff like that, Shannara is probably down in the cellar.