The isekai genre has gotten very popular within anime, and it's similarly gotten just as old. Despite the amount of fans who can't get enough of the genre, there are just as many who avoid it like the plague. This has required isekai anime to get creative and splice in some different subgenres. Sadly, this didn't work in the favor of a series that premiered before the genre really hit it big.
Source:https://www.cbr.com/how-knight-magic-combined-magic-with-mecha/