It _would_ be bigger and eat more RAM and CPU. But that does not imply "shittier".
There are parameters like dev time, skills available in the market, familiarity, the JS ecosystem etc that sometimes outweigh the disadvantage of being bigger/slower.
You're pointing out the disadvantages in isolation which is not a balanced take.
A sensible take wouldn't pick one or the other as unilaterally better regarding the abstract context of what a good product is. The web as a platform is categorically amazing for building UIs, and if you chose continued to choose it as the frontend for a much more measurably performant search backend, that could be a fantastic product choice, as long as you do both parts right.
And this isn't Rust zealotry! I think this goes for any memory-safe AoT language that has a good ecosystem (e.g. Go or C#): why use JavaScript when other languages do it better?
Sounds like Rust zealotry to me, followed by a mild attempt to walk it back.
Not really. Nobody is rewriting GUI apps in Assembly, the reasons are obvious.
However, you could use Rust compiled to WASM in an Electron app, therefore the two aren’t even mutually exclusive.
For desktop apps UI quality and rendering speed is paramount. There's a lot of stuff buried inside Chrome that makes graphics fast, for example, deep integration with every operating systems compositing engine, hardware accelerated video playback that is integrated with the rendering engine, optimized font rendering... a lot of stuff.
If your Rust UI library is as advanced and well optimized as Blink, then yes, maybe. But that's pretty unlikely given the amount of work that goes into the Chrome graphics stack. You absolutely can beat Chrome in theory, by avoiding the overhead of the sandbox and using hardware features that the web doesn't expose. But if you just implement a regular ordinary UI toolkit with Rust, it's not necessarily going to be faster from the end user's perspective (they rarely care about things like disk space unless they're on a Windows roaming account and Electron installed itself there).
The fact that you just draw on the screen instead of doing whatever html parsing / DOM/IR is probably doing it? And doing rendering on the gpu means extra delay in the processing moving from cpu to gpu and being a frame behind because of vsync.
For any non-trivial case where I can enable GPU acceleration for an app, it's been anywhere from equivalent to much more responsive.
What apps have you experienced delays with by enabling GPU acceleration?
"Write your frontend in JavaScript, application logic in Rust, and integrate deep into the system with Swift and Kotlin."
"Bring your existing web stack to Tauri or start that new dream project. Tauri supports any frontend framework so you don’t need to change your stack."
"By using the OS’s native web renderer, the size of a Tauri app can be little as 600KB."
So you write your frontend with familiar web technology and your backend in Rust, although it's all running in one executable.
I am curious if it would be all that much worse if your backend was also JavaScript, let's say in Node.js, but it certainly depends on what that back end is doing.
I took that as the somewhat the point, and I think it was insightful. Your app will still be worse, but worse as result of your poor technology choices, not the arguments made here. Put together it may still be a bad move, but you would still get the greenfield effect.