I.e. I would say the probability is zero that because WASM exists other existing complexity of browsers will be removed.
Because the web is so vast, if you once add a feature to browsers you can never remove it because that would break an unknown amount of websites, or even intranet sites.
So now we have wasm + N other subsystems, so N+1, and the security of N+1 systems is less than that of N.
We break/deprecate the web all the time. Web backwards compatibility is a myth, it's just that wo don't get any calls from the 90s complaining that their dogs website broke.
But isn't it a case of XKCD 927? https://xkcd.com/927/
I.e. I would say the probability is zero that because WASM exists other existing complexity of browsers will be removed.
Because the web is so vast, if you once add a feature to browsers you can never remove it because that would break an unknown amount of websites, or even intranet sites.
So now we have wasm + N other subsystems, so N+1, and the security of N+1 systems is less than that of N.