Basically, no. The issue was never the instruction set, you still have to support the interface and the OS which nobody is bothered to do because cost benefit.
Changing the chip isn't going to change the code base of the operating system.
Some iOS and Android games support keyboard/mouse I think. You can also potentially map mouse movement to joystick movement for relative games like shooters. There are people who play pubg mobile on desktop with BlueShift or whatever already. Barring that maybe there will be a market for apps that make playing iOS games with keyboard and mouse easier.
Changing the chip isn't going to change the code base of the operating system.