Need advice for a gpu card

atm i run war thunder almost maxed out with ssaa on 4x (this is a must for me since it makes the game look so good) with a rtx 4070. (fps between 90-120)
im buying a new gpu for my oldest kid probably a amd 7900 GRE if i take the 7900 GRE and give him my 4070 would it improve my FPS?
and are driver issues still a thing for amd cards?
1440p

LF

yes but why do u ask?