I think regardless of the type of cabinet, supervectoring / profile 35b would need new line cards and a new vectoring engine. I thought the crosstalk problem gets worse with higher frequencies, so it did need more powerful vectoring. Certainly the vectoring engine has more processing to do to handle the increased bandwidth of the signals.
Probably supervectoring is less "future proof", because there's nothing beyond it with VDSL2, whereas G.fast continues to be developed.