I’m curious where COSMIC will land. It takes the previous iteration of Pop!, which used a lot of extensions on top of GNOME, and instead uses Rust as its main implementation language. So far, its applications have seemed very snappy, but that of course doesn’t mean that they are light on the RAM usage when it comes to a 2GB computer.
Along those same lines, the Lapce IDE is fairly lightweight. It’s no vim, but it is a very good GUI. I am running it on my 10 year old laptop, 8 GB, and it is noticeably more performant than VS Code on a new computer.