I started watching King Of the Hill a few weeks ago in order to see the whole series before starting the new season, and at season 4 mark, I can't for the life of me understand why people dislike/hate peggy hill when she's not alone with the flaws she's criticized of even in her immediate family.
Nevermind, starting to see that. The further this show gets, the more self centered she gets. I think the pyramid scheme episode kinda broke the camel's back for me, the way she took advantage of Bill in order to get into that event just so that she could look good by basically stealing the credit.
She's still got her noble moments, such as the time hank got suspended from the shop teacher substitute position and she decided to run for the "Substitute Teacher Of The Year" award on his behalf as "mrs. Hank Hill", but even then there were clear ulterior motives (shown by her speech in the end)
She's still a great character in the situations where she doesn't let her ego get in the way, but she could really benefit from having some humility and admitting she's sometimes wrong.
She gets REALLY self centered from season 8 onwards. Even the writers said they regretted doubling down on the trait in the later seasons. I still love Peggy and Peggy episodes, and she still has her moments (season 11’s drag queen episode) but it’s pretty heavy in the later episodes.