A Dart-like language designed with WASM as target will make sense now but I think Dart(as it is now)is already doomed to die. The performance promissed is just not there.
Javascript compiled from Dart is as fast as normal Js, in some cases faster. And in the server it outperforms Node according to the Techempower benchmarks. https://www.techempower.com/benchmarks/
In some cases is slower. Last time I've checked large apps were freezing on safari. The point is that it's not signifiantly faster than js so I think it's safe to say that it failed its main objective.
I think this[0] summarises the main objective of Dart. Having said that I fail to see how it succeeded. Maybe it helped JavaScript evolve a bit but IOS development experience and performance is still vastly superior to Dart/JavaScript/Web.
[0] `The emergence of compelling alternative platforms like iOS has meant that the web platform must compete on its merits, not just its reach. Javascript as it exists today will likely not be a viable solution long-term. `
Lars Bak made V8, and both Kasper Lund and Lars Bak contributed the HotSpot VM. And if you don't consider Gilad Bracha (Who works on the Dart Language Specification) to be a language designer, you probably don't have a clue what he has done.
How is that? As far as I can remember performance was always the main reason. The main contributor previously worked on hotspot. It was argued that javascript hit the limits on performance and you need a clean slate, especially due the low power of the mobile devices. "Batteries included" and fixing the javascript syntatic issues was presented as secondary objective. This might have been changed after the VM was dropped from the project. Dart was supposed to be a response to native apps which failed miserably. It's a well design ecosystem for sure but it can't even compete with javascript, let alone native apps.
You are right. Perhaps I heard only I wanted to hear. Anyway here is a talk about performance so definitely it was marketed as a high performance language for the web too.
https://www.infoq.com/presentations/Performance-V8-Dart
The keyword you are looking for is Dartium (Chrome with Dart support compiled), and if you are benchmarking a Dart app in Dartium vs. a JS app in any of the browsers, chances are the Dartium app will be faster. The technical goal was achieved, the political support lacked.
Even with Dartium it didn't reach a speed close to native. I don't doubt that if more effort would be put in the VM the perf could get better but as it is now Dartium is no longer an option.
There is nothing in dart that would freeze it on safari, except that large app are slow on safari, regardless of dart. Btw. the linked benchmarks are server-side.
I think the performance is there, it's just gained from JS VM optimizations instead of an alternative VM in the browser. The advantage is that it gets the benefit on all browsers (even those that would never add a Dart VM) and all other xxxToJS languages get the benefit as well.
Dart has enough other advantages so being on par with others on performance doesn't mean Dart has to die.