If you want fixed 1080p and nothing else in ryujinx (or yuzu)... you take the disabling dynamic res patch from the first post (under Spoiler: patches made by the community) and put it in the mods folder like so:
MOD_NAME/exefs/A7643F3B7D8EE906BDFE18C3DDBA42A300000000000000000000000000000000.ips...
I may try the new ram site, and download more RAM to my Switch. Not sure if ddr3 is the right ram
for it tho. Edit- no it uses floppy Ram, just like @AncientBoi