Anime

Sword Art Online taught publishers that people really want bland wish-fulfillment stuff where the hero just steamrolls any problems that shows up and then gets all the girls. Of course SAO had other things going for it, like good animation and a great soundtrack, but that isn't what they can easily copy.

Shield Hero taught publishers that people want that but also with the main character owning slaves for some reason.

Anyways, due to these two things isekai has been almost universally weird af lately. That said, it's not all bad. I liked The Eminence in Shadow, but I recommend the manga adaptation over the anime. The mangaka just has a really good sense of comedic timing. I've also heard good things about Shangri-la Frontier. There are a few more good isekai if you look at the pre-SAO era. Vision of Escaflowne was really good, as long as you come in with the expectation that this is a shoujo mech isekai so it'll have a somewhat different feel to it.

Of course, that's if you're stuck on wanting to watch/read isekai. There's been tons of great stuff coming out every year that has nothing to do with isekai. My favorites from the last 5 years have been:

• 2020 - Keep Your Hands Off Eizouken! - A team of high school girls form a club and set out to make whatever anime they can with their limited resources
• 2021 - Vivy -Fluorite Eye's Song- - The first AI-powered humanoid robot tries to prevent the robot apocalypse
• 2022 - Chainsaw Man - A sad boy has a wild (and bad) time. Honorable mentions go to Spy x Family and Bocchi the Rock. It was a strong year.
• 2023 - Skip and Loafer - A book-smart girl from the country moves to Tokyo for a better high school and adapts to city life
• 2024 - LOOK BACK - A story about 2 artists. Honestly this year was stacked too, so honorable mentions go to Bang Brave Bang Bravern! (big gay robots), DAN DA DAN (romance, yokai, and aliens), and Delicious in Dungeon/Dungeon Meshi (traditional fantasy, but really well executed).

Notably even though every year a whole pile of isekai gets released not one of them made it into that list. I'd avoid them as a general rule for a while, except when you hear a lot of people recommending a specific specimen.