I’m a fan of breath of the wild / totk and didn’t really enjoy genshin impact. They really are very different games with a superficially similar cel shaded art style and open world. (But even then Nintendo’s art direction is totally different)

There is nothing about Genshin Impact that is related to Zelda in terms of technology. The style is similar but style similarities isn't addressable through patents.

BOTW/TOTK have excellent implementation and aesthetics but there is nothing about them that is technically unique or worthy of a patent.

I blame Nintendo because I think that they should compete in the market by making good games, as opposed to trying to stop other people from doing so themselves by abusing the legal system against competitors.

Do you think Nintendo has or needs a monopoly on open-world cartoon-styled games?

They can do what everyone else does. Make new games.