It's not clear to me why you would want your editor to run in as many environments as possible unless you're a system administrator? Generally, most of us do our serious coding work on the major OS platforms and we would want a native editor that takes advantage of those platforms and the hardware they tend to run on maximally; if we need to edit something on some other box elsewhere, we could either use Zed's remote development system or just use MicroEmaca Nano or VI depending on which key bindings were used to.
The advantage I find personally, at least compared to something like emacs, is not just that you get high fidelity scrolling, but that the editor can open 60,000 line code files instantaneously syntax highlight all of it using trees that are and be butter smooth and responsive the entire time I'm searching through making multi-cursor edits or moving through the file. As well as being able to open for instance log files that are multi-megabytes large without having to worry about anything.
Plus, Zed has a lot of refinements and features over other editors, even if you discount the benefits of GPUI. I've spoken at length before about why I think its approach to coding agents is the best at sort of enhancing the human in the loop and keeping you in a flow state and preventing skill degradation[0], but I also think the range and design of the editing actions are better than almost all modern text editors, closer to what something like Emacs provides, and the UI is overall more streamlined and pleasant to use than something like VS Code, even though it's generally the same philosophy. There's also the collaboration features and the edit predictions.
[0]: https://news.ycombinator.com/item?id=46995110