An excellent deleted comment said "Star Wars is incestuous."

Not the Luke / Leia thing. The sequels. The first movie is shamelessly a blender full of George Lucas's favorite things. The sequels draw from all kinds of fiction, especially foreign movies that all these nerd-ass 70s directors loved. They were doing their own thing, shaped by a wide variety of influences. Even the prequels were a pastiche of bygone dramatic storytelling techniques, most of which were bygone for good reason, and some of which were just thinly-disguised racism. But you can see trashy jetpack serials in Phantom Menace as clearly as you can see trashy jungle adventures in Indiana Jones.

The Star Wars sequels were made by people whose only influences were Star Wars. Or at least Star Wars and the inevitable avalanche of movies directly rooted in Star Wars. It's just a tangle of self-interested ideas that only works for people who also grew up mired in that monoculture. Anyone else is unsure why they'd care about these characters in this situation. Or they have uncomfortable questions about how this setting hasn't changed in forty years. The middle one at least tried to use Star Wars as a critique of its own status quo, and that just made everyone mad.

Anime c. 2010 was deep in a phase where the primary influence for new creators was old anime. If you'd grown up with it and other stuff, you could be Anno, and deconstruct tropes into some really poignant... trolling, frankly, but that's just Anno being a cock. But if all you know is how things are then that's how you'll figure they're supposed to be. Everything was set in a school and lightly dusted with superpowers because that's just how stories do. There was no recognition that the original projects picked magic as a metaphor for some difficult coming-of-age thing that made a familiar setting both a useful framing device and an ironic contrast. And apocalyptic stories (which may also somehow be set in interminable high schools with magical realism) aren't reflective of any cultural concerns for the future or an excuse to reflect on current biases by isolating them from our modern present. They're just cool to look at and a neat place for explosions to happen to bad guys.

Isekais aren't the worst this has been - but they're the most obvious this has been. It's a frankly cheap gimmick for establishing an audience-insert main character who's inherently different and superior in some way. On some level I applaud the blatant directness. But when fffucking everybody does it, even in settings where there's really not a reason for the protagonist to be from elsewhere or Like You But, it reveals how many people think that's just decoration. They do not understand why a story does this. They may not recognize it as a choice. Like getting Wizard Of Oz'd is just the paper you write the words on.

Basically, isekais are the useless "nobody:" of anime. They're a symptom of a deeper problem where people can't communicate ideas except in relation to prior examples. And what else do we expect, when the people who grew up writing Doctor Who fanfiction take charge of Doctor actual Who?