It really depends whether he got the devs of “Lutris, Heroic, Legendary, Bottles, etc.” to agree to use the unified runtime before starting this project. As long as he gets most of the big players to join then it will actually become the only standard worth using.
I think upgrading the RAM as you mentioned is going to make a big difference. While the physical RAM might be soldered to the motherboard, you could buy a fairly cheap SD card or USB and set the system up to use that as virtual memory. It won’t be as fast as actual RAM but it might help and large SD cards are honestly really cheap these days.