VS code is a good app in spite of using electron, not because of it. There’s no reason a simple plaintext editor needs to allocate 300MB of ram even without extensions just to launch, and there is definitely no reason a plaintext editor should require compiling chromium to build from source.
Slack is fine, but only when you exclusively use slack. Throw in an actual browser, discord, VS Code, Whatsapp, teams (?), etc. each with their own chromium instance and now your 16GB of ram are being eaten up at idle.