It would work a lot better than what mobile browsers are doing now. The only websites that can be argued to be helped by that were those with fixed table layout

It would work a lot better than what mobile browsers are doing now. The only websites that can be argued to be helped by that were those with fixed table layouts - but those are still pretty unusable even with the standards-noncompliant hack. And websites that were mobile-compatible before like plain HTML sites like the TFA are needlessly broken.