Yeah totally, I'm sure there are multiple aspects to it. I don't think Nexomon counts as a rip-off game, a rip-off idea maybe? poorly mimicking the original game is ,for me at least, the one thing that separates a rip-off from a clone or a spiritual successor etc.
The intention being, most of the time, riding on the popularity of the original to success.
I also wouldn't generally consider fan games to be rip-offs.
Pussy so fire, be running on 5200Mhz
comes with built in water cooling