>>2231513That's not what's being said.
The artist is proposing two models, the latter of which reflects how the creative industries (generally) operate.
Paying royalties for the use of intellectual property is actually the norm by large.
Also worth noting, even a flat fee doesn't give you unilateral ownership of that model unless that's what is specifically agreed. Payment (if demanded) doesn't affect your basic intellectual property rights as an artist, no matter how it's collected.
Usually an artist will effectively stipulate "you can use it for personal use, live streaming, ect" but if you want to use the model on an advert with, idk, Burger King, you'd have to negotiate with the artist again.
The intelligent thing to do as a vtuber though, is to ensure you make the design of your character yourself. That way you can still commission someone else to make art for your Burger King ad. Or if you go outwith the terms of the original contract around your model. and your model designer isn't open to renegotiations, you can commission someone else to for a new model.