[eyelidlessness]

It had to be incompatible with CommonJS regardless of top level await. There is no imaginable scenario where browsers would ship a module system with synchronous request and resolution semantics. A module graph can be arbitrarily deep, meaning that synchronous modules would block page load for arbitrarily deep network waterfalls. That’s a complete non-starter.

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.