I agree about chocolate. I rarely bother with a bar of chocolate now because they either taste greasy or acidic.
I also agree with;
Once Upon A Time. The show has a chaotic quality, almost like it's being improvised scene to scene. I persevered for a long while (felt like eons) because there were little diamonds among the dross, like Rumple taking Cruella and Ursula through a drive through, but it got too tedious watching the characters going round in circles.
Frasier. I liked the Niles and Daphne love story at first, but for me the show nosedived with the way they tried to conceal Jane Leeve's pregnancy. The scene where three grown men can't pick her up off the floor embarrassed me to watch. I also hated the way the male characters consistently slutshamed Ros while congratulating themselves on their endless conquests.
Gossip Girl. The big reveal made no sense. I won't give it away in case someone is yet to watch it, but it was impossible for that person to be GG! (And I hated Chuck. I didn't see any great evolution. He started as an attempted rapist, and he treated Blair horribly, before, during, and after their relationship. They only ended up together to tie up their story thread.)
I can't recall what point it started going a bit downhill, maybe series 7 or 8? I still like a lot of the storylines but Monica turned into this horrible screechy caricature who did nothing but clean and be a bit of a bitch. Chandler got all red and...boring? Phoebe got a bit blah.
And Joey had a frontal lobotomy at some point. He started out as a normal person, and ended up not being able to function without assistance.