> neither does it expect the publisher to provide resources for the said videogame once they discontinue it while leaving it in a reasonably functional (playable) state
This could not possibly mean forcing e.g. WoW to keep their servers running forever. It just means that if your game could be written without a phone home "feature", then it must be.
In other words, it would not justify an increased price. Publishers may choose to increase the price, because they don't actually need a justification in order to do that. But this legal change would not be a good reason.