Given that, top-level await is a sensible affordance, which you’d have to go out of your way to block because async modules already have the same semantics.

Recently, Node has compromised by allowing ESM to be loaded synchronously absent TLA, but that’s only feasible because Node is loading those models from the file system, rather than any network-accessible location (and because it already has those semantics for CJS). That compromise makes sense locally, too. But it still doesn’t make sense in a browser.

But also, there's a special place in hell for the people that decided to add default exports, "export * from" and top level await.

Commonjs is also very weird as a "module" instance can be reassigned to a reference of another module

module.exports = require('./foo')

and there's no way to do this in ESM (for good reason, but also no one warned us). In fact major projects like React use CJS exports and the entire project cannot be optimized by bundlers. So, rather than porting to ESM, they created a compiler LOL

I'm convinced that 90% of the JavaScript ecosystem only exists to build tools for itself. It's tools all the way down

There's a certain irony to being able to introduce you to the term "Baader-Meinhof Phenomenon" (which is the more-common name for what I assume you're referring to, as Google searches for "Yellow Bus Syndrome" didn't bring anything up for me). Now you know the name, you'll see it everywhere!

Although JavaScript is still an interpreted language, it basically gets "compiled" when the browser parses the bundle. On the surface, the only thing WebAssembly automatically gets you is you get to skip the runtime compilation phase.

I might be talking out of my ass, so take this with a grain of salt, but I wouldn't be surprised if once we start collecting real data on this stuff, SOME WebAssembly code could actually run slower than just using JS code. My hypothesis is that if you're starting with non-JavaScript code, you might be doing things in that language that would be slower to do the same way in JavaScript. I'm thinking of things like Array.map(), .filter() etc. ... which are hyper-optimized in V8. If you're taking an algorithm from C code or something which then gets compiled to WebAssembly, it's not an automatic given that it's going to compile to WebAssembly that is just as optimized as what V8 would do when it comes across those API calls. Again, this is just a hypothesis and I could be way off base.

In any case, what we need is real world data. I have no doubt that for certain applications you can probably avoid land mines by hiring devs who are experienced building certain performance-critical things at a lower-level than your average JS dev... and their experience in those languages may transfer very well to the browser. In this scenario, you're not getting huge perf wins from using WebAssembly per-se... you're getting huge perf wins for not doing typical stupid, lazy, ignorant things that most average JS devs do ... like cloning large objects using the spread operator and then doing that over and over and over again "because immutability."