In a sense we are very lucky these days these companies even extend support as long as they did for this particular case - in the future I think the window between "next gen version release" and the deprecation of the previous version will get smaller and smaller.
There is no financial incentive for them to keep the servers alive, so they don't. Thusly video game manufacturers should avoid making being online a necessity to play the game - but that's unlikely to get better either.
Not sure the solution, other than to provide "offline mode" for most games that really really do not need to be online other than to force players into some microtransaction/tracking hell.