vscodium isn't immune to the problem tbh - put it behind a gating proxy (mitmproxy or something is probably easiest) and watch just how chatty it still is (for plugin mechanism etc)

the entire design of how the vscode ecocystem is put together is in service of their telemetry aims, imo. they may argue it's "for safety" or whatever, but it's just control and surveillance. alternative options that don't do this shit exist and operate just fine