So you're saying cheating could/does include Netorase but not Netorare? That's an unreasonable expectation and probably a naive one.
How it exists now the tag system is wrong so you are making a mistake following it like you do. But to each their own.
Stop putting words in my mouth. Cheating is used on netorare games, netorase game, netori games, and somtimes its not. Cheating is just too broad of a tag so devs don't know if they need it or not.
Not all NTR is cheating because your mom is not cheating on you when she fucks your bully, but that would still be Netorare.
Cuckold is not cheating because the girl has permission, but Netorase is a mixed bag. She has permission, but to be Netorase the MC will lose her, either physically or emotionally where she stays with him but is in love with the bull. Thats kinda sorta cheating, but pretty subjective in how you want to apply that logic.
Netori is cheating from the perspective of the girl, but not the MC, and most tags are generally from the MCs perspective, so do we use cheating here? Probably so, but maybe not, who the hell knows.
But it all leads to the same thing, cheating is a shitty tag that doesn't help you narrow down a search range, it's too broad.