That's because VS Code is hiding everything behind a bunch of non-real-time tricks of perception. Zed is giving you actual real-time feedback.
"Whom the gods wish to destroy, they give real-time data."
The overwhelming majority of the population cannot perceive anything over 90 Hz. Those that can are overwhelmingly skewed towards under 30 years old. Fighter pilots have a floor of something like 200hz for an idea of how rare it is. Just fun info.
I have 3 different displays on my desk, and they are 60hz 120hz and 240hz.
The difference between them when scrolling is.. obvious. I'm in my 40s. I'd love to see a study demonstrating that my ability to perceive this is some rare capability - that's very hard for me to believe.
Comparing side-by-side is always easier. The question is never that (should not be). The question is, would you approach a random coworker's desktop and really, sincerely, notice if they have a 120 vs a 144 Hz (or 240) monitor?
I'd say maybe if you are a professional in the sector of multimedia processing, you would be so accostumed to the smoothness of high FPS that a meager 60 fps monitor would be obviously noticeable. But for the untrained eye, I feel most people wouldn't even notice in a random scenario like that, whether the screen is 60 or 120 (and that's the range with highest ROI on FPS increments!)
I spent an admittedly tiny amount of time looking into the Zed scrolling stutters after experiencing them myself and I think it's just a matter of their line layout caching not being as good (perhaps unsurprisingly) as the Chromium/WebKit layout engine. It's especially noticeable if you have word wrapped files with lines >10kb in length (yeah, don't ask).
Zed is also at the bleeding edge of rust GUI development, which doesn't have the same mature libraries as other low-level languages. I'll give them the longer-term benefit of the doubt, but the attention to detail does matter.
To be fair, one could say the same for Zig, but Ghostty does extremely well in this regards. While it maybe doesn't have the same complexity that Zed does, it does have to deal with a lot of historical cruft of terminal emulation...
"Whom the gods wish to destroy, they give real-time data."
The overwhelming majority of the population cannot perceive anything over 90 Hz. Those that can are overwhelmingly skewed towards under 30 years old. Fighter pilots have a floor of something like 200hz for an idea of how rare it is. Just fun info.