I think performance complaints about vscode are either from bad extensions/too many OR poor system resources.

When I first started my current job, they gave me a laptop that was under specced due to the high performance laptops being back ordered.

Vscode performed really poorly, but so did everything else. MS teams was the worst offender by far. I had to close every other application in order to join a meeting, lol

Who knew that having 100% CPU and 100% ram usage would slow applications down...