Sublime Text (https://www.sublimetext.com/) is fantastic. Startup time is instant. RAM usage is low. It'll do syntax highlighting out of the box. And with a few extensions (optional) it'll do almost everything that VS Code does (sublime-lsp is key for IDE-like functionality). It's also great for large files so long as they'll fit in RAM.
Bonus: it works cross platform (windows/mac/linux).
Bonus: it works cross platform (windows/mac/linux).