If Zed would not exist, I would be using helix, neovim, or emacs as I did before.
It remains to be seen if Zed can avoid that though.
If you don't feel that VSCode is slow, it's because you are used to it.
I don't think this is a fair claim. When you start doing an apples to apples comparison, that is to say make full use of IDE and auto-completion features it's difficult to see a difference given that the latency and speed of the plugins starts to dominate any millisecond difference in input latency or rendering speed.
Seems to work the same for me in VSCode, CLion, and nvim. I don't doubt that you have issues with it (I've experienced slow editors & laggy input, it sucks) but I don't think it's inherent to VSCode. Doesn't mean it's not a bug, but if I had that issue I'd try with no extensions to verify, then binary search disabling the extensions I want until I find the one causing the lag.