My system monitor says it's using 1.3GBs after warming up, and even forcefully reindexing a big C++ project.

I don't think VSCode will use 400MBs with that amount of code, plus electron, plus all the LSP stuff you run beneath it.

In that state Eclipse will fit into a 6GB system just fine. I'd love to try that at a VM right now, but I don't have the time, unfortunately :)