This is dangerously close to a “nothing to hide” argument. The issue with telemetry is that it’s difficult to do it right, and often it ends up just siphoning data that ends up being abused or mishandled. Having this be opt-in raises questions of consent.
If you think there is something that it might upload that you might not like, please let us know. Here's the extension - https://github.com/Microsoft/vscode-extension-telemetry. You can check for usages here - https://github.com/Microsoft/vscode
There is plenty of personal information that I never want shared with anyone, like my location history, who I speak to and so on. But what shortcuts I use, what features I use in an application, after it's been anonymized? I have "nothing to hide" there.
Also, if you're so worried about being de-anonymized, then opt-out?
[1] - https://news.ycombinator.com/item?id=19427773
[2] - https://news.ycombinator.com/item?id=19109815 (this one is great, because it's a task raised on dotnet cli, but posted on the thread about VS Code release notes)
They disclose vulnerabilities to US government agencies first and stil to this day have no transparency about what information they share with governments.
Wow do you actually believe that? Have we forgotten about NSA KEY already?