Yeah WebAssembly enables casual gamers, gamers on Macs (especially on newer M1/M2 devices with limited game compatibility natively) and students on Chromebooks to jump into a game in a low friction manner. And this isn't even mentioning being able to reach mobile devices, which represents the largest portion of revenue in the games industry today.
Couple this with the fact that developers won't have to pay a 30% fee for distribution on the web, and you have the recipe for the next big games platform that's hardware agnostic by default. Very disruptive stuff.