At a mechanical level isekai in webnovel form lets you introduce the reader to a new world much more quickly and easily than if the MC were in that world with no reference to our own.
It's why I think it's so popular, especially when coupled with a "System" as in litrpg which accelerates that even more.
It's easy on the creators primarily, they get to skip a lot of steps and don't have to explain away things like cell phones.
For consumers, they get quantity.
Although it shouldn't be impossible, it seems really hard to get any kind of real quality out of isekai stories. Usually the stakes are low and the setting is surprisingly similar (even though having a different setting is ostensibly the entire reason for the genre). All you end up with is variety in characters, and even then there are common tropes.
Apple's Numbers and Pages seem very far from ideal. Zoho didn't quite work for me. Maybe I should try Clickup.