For digital copies, they could bury this into the EULA and make it a requirement that you agree to it before you make your purchase (IIRC some storefronts do this already).
However for physical copies I suppose there could be a case made if the duration of support was not disclosed at the time of purchase (or it was not printed somewhere on the outside of the packaging).
Government Response - Petition: Require videogame publishers to keep games they have sold in a working state (petition.parliament.uk)
tl;dr: we will do nothing about it...