Zed team is writing their own in-house GUI stack [1] that leverages the computer's GPU with minimal middleware in-between. It's a lot of work short-term but IMO the payoff would be huge if they establish themselves. I imagine they could poke into the user-facing OS sector if their human-agent interaction is smooth. (I have not tried it yet though)

[1]: https://www.gpui.rs

Sublime did that almost 20 years ago.

What about the text editing part?

It's written from scratch in Rust. It's super fast, polished, etc. A world of difference compared to VSCode.

it's fast

I am very sensitive to input latency and performance but after comparing Zed and VS Code for a while I really couldn't find any reason to stick with Zed. It's been a year or so since I last tried it but VSC just lets me do way more while still, IMO, having a nice, clean UI. I never notice any performance or key input latency with VSC.

If you work in a team there are some pretty good remote collaboration tooling built into Zed.

And it can load staggeringly large files without falling over on itself.