MS still slurping code into Copilot from [...] telemetry in VSCode.
Would you happen to have a source for that?
At a cursory glance, it looks like VSCode only does that if you're using Copilot, but if you don't have the extension installed they aren't.
Kate has native LSP support, which by default uses "typescript-language-server" for JavaScript. As I don't really do much JavaScript stuff I can't say how well it works, or if it works with those particular frameworks.