[lapser]

There's nothing wrong with that. VSCode will certainly have a lot more development that a fork would ever see. So the best thing to do here is simply build VSCode with all proprietary stuff removed.

[hospitalJail]

The plugins are the real value, and those are built behind the M$ fortress.

[BearOso]

Clangd and rust-analyzer plugins aren't made by MS. Python has a couple separate ones, one of which the official Microsoft plugin uses. I think the only language needing a MS plugin is TypeScript, which is a MS language anyway.