All I'm seeing is that Chrome apparently is failing to properly sandbox websites against extension fingerprinting.

Sure, this can be solved at the legal layer, but in this case, there seems to be a much simpler and more effective technical solution, so why not pursue that instead?

Well, the developers of Chrome aren't exactly incentivized to prevent tracking (though perhaps tracking done by their competitors). But anyway, you can try to prevent it with a technical solution while also being outraged that they did it. If someone has their home broken into, perhaps they should have better locks, but the burglar is still responsible for their actions.