Only thinking of things a lot of people like:
Rogue One - the bits that are good aren't original and the bits that are original aren't good. It's carried by the tone of a war film and more Empire Strikes Back porn than JJ Abrams uses of ANH in TFA
The Big Bang Theory - I've heard it described as a "Geek minstrel show"
The Avengers films - I've a soft spot for the first. But they are a confusing mess with too many characters and contrived storytelling. I've special hate for the way Thanos is never shown to be wrong, just less powerful
Joker - another film where the bits that are good aren't original and the bits that are original aren't good.
South Park - I didn't like edgy 90s nihilism even back in the 90s. And it's aged badly.
Gone with the Wind - I'm not sure which is worse; how little I like the leads or how little I like the setting
Tiger King - car crash TV about a bunch of horrible people
The Mandalorean - I've mixed feelings about this one. It's weapons grade nostalgia (hey, I own Smash Ultimate) with a good premise, good acting, and about as much progression as an 80s TV series. Each episode is fine as long as you watch them a week apart and don't binge.
Also there are a number of things where I'd recommend people see one work by the author and stop there. Joss Whedon springs to mind (I'll recommend Buffy S1-5), as does JJ Abrams (for me his best is Alias S1-2 but that's also the first I saw), as does Aaron Sorkin (although The West Wing really does not hold up) and Stephen Moffatt.
Dishonourable mentions for being targeted nerd porn (although without onscreen sex): Chuck and The West Wing. I can watch both of them but am well aware I'm being pandered to and it makes them feel slightly icky.
On preview the parts of Transformers that aged well were the UK Gen 1 comic series (which is pretty intricate and continuity heavy) and the original movie. The one where there are actual consequences, starting with the death of Optimus Prime, callbacks, conceptual sci-fi like the Universal Greeting, and a discussion of leadership and how it means going forward in the face of adversity, complete with Devo's Dare To Be Stupid as a theme song. Also I didn't realise the D&D cartoon was popular.