No, the issue isn't because it's Koikatsu, it's because it's the same format, same sandbox, and almost always a parody of existing media, with cards taken from somewhere else. If you take a look at the developer notes, you notice it's almost exactly the same, and also this "dev" was also the one who made Z Fighter Trainer.
If you look at this list of games you will slowly see how similar all these games are:
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All if this is just recycled shit using Evaan's cards or other cards. Now do you see where I'm coming from?