So much frontend JS has been packed and minified now that I’m not sure it will make that much difference. Reviewing Open Source code is still a far superior way to understand how code works, imo.
It is possible to disable half of the paywalls on the web just by looking at the JS code. I can see why certain parties would push really hard to introduce Webassembly. The performance argument is just a pretext because today's jit compilers for Javascript are really good.
Shhh! Don't tell them!