Yuzu was fully open source software up until the very moment it was removed from all host sites. Nintendo cannot retroactively change its open source license, so it's completely legal and falls within the terms of that license to create new...
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