Now don't get me wrong, standard qualifier from an avid anime watcher, yes, isekai fantasy anime was always generally considered pretty trash. I consider it the junk food of anime where you know it's terrible for you but you kind of watch it anyway and I've sometimes found it entertaining because the studios redeem the shows with decent character writing and backstories.
The last couple of shows overall have been so bad it's surprising and it's almost woke levels of shittiness and I hope this is just a blip because it's summer anime but how do you manage to fuck up such a basic premise as making an interesting fantasy story? It doesn't have to be original or even amazing, just make it decent. I'm seeing the newer stuff come out and it's like they've shamelessly copy-pasted scenes and plastered them onto the new characters and their budget is clearly very low because you've got the poorly rendered 3D monsters problem again.
Maybe Frieren raised my expectations way too much but even by Isekai trash anime standards it's been a particularly poor showing at the moment. Once you notice all the shit they do to cut corners in animation like literal slideshow scenes with audio ( It's usually a hotspring scene or they're 'wandering' around a market ) it's really hard to unsee it and I despise studios that do this.
It depends on two things for a good fantasy anime:
Quality of original content
Quality of adaptation
Because of how popular fantasy isekai is the same way regression is popular in South Korea and cultivation in China, some studios think they can cut corners leading to people thinking that fantasy in general is basic and leads to a self fulfilling stigma. I've seen TOO many good stories ruined by cost cutting studios that the deserve a 'Fruit Baskets' treatment and quality adaptation.
There are some EXCELLENT stories that have fantasy elements still available, one I'd love to see a quality adaptation is The Galactic Navy Officer becomes an adventurer as it combines sci fi WITH fantasy with commander of an AI Starship having to land on a planet after a sustaining damage to find it a medieval like society with magic. That would be a great anime IF they treated it right.
I feel like the Japanese have been allergic to sci-fi lately, if it's not any kind of mecha they're not interested, even though they've done some fantastic sci-fi anime in the past.
It's harder to do escapism in Sci fi than fantasy and Asia REALLY loves escapism right now.