I love Blanchett, but what she wants will of course never happen, and is antithetical to the point of the Oscars. Obviously we can imagine a time when the Oscars are no longer on linear television, though for all the recent gnashing of teeth I expect the Oscars to continue on linear TV for as long as linear TV continues to be a mass form of media.
What she wants is for the Oscars to be a private party, not just not on TV. That has not been true since 1929, the first Oscars. From 1930 to 1952 it was on the radio, which was the most influential mass media, then television.
The Oscars exist to market films and film makers and to promote and unify the film making community. They help make people like Blanchett millions of dollars. Part of the price is being observed by the masses for 3.5 hours. The after parties are relatively private for the kind of experience she seems to be asking for.