Yes, I don’t think other clubs are quite so precious about wage structure, plus not many have of them have other genuine world class players like VVD and Alisson to consider.
The only way Madrid can pay 700k would to Mbappe is if the total outlay of 200M or so doesn’t include a fee. For Salah, no fee needed brings Barcelona into the picture, at probably the suggested 500kpw for 4-5 years. That’s want he wants imo, the rest is just the usual dance.