Sometimes, a somewhat obscure Linux distribution might be just what you're looking for. Is either CachyOS or Nobara the one?
After years of trying lightweight Linux distros, a modified Windows setup finally made my old laptop enjoyable again.
Sudo lets you run any terminal command as another user — hence "substitute user" — but the default and most common use for it ...
For Linux and MacOS, Fresh is the best of both worlds - a terminal text editor with GUI-like options. I'm all for it.