I think in the case of forced agreements (both Roku not having a way to select disagree and disabling all hardware functionality until you agree, and blizzard not allowing login to existing games including non-live service ones) no reasonable court should be viewing this as freely accepting the new conditions.

If you buy a new game with those conditions, sure you should be able to get a full refund though, and you could argue it for ongoing live service games where you pay monthly that it's acceptable to change the conditions with some notice ahead of time. If you don't accept you can no longer use the ongoing paid for features, I expect a court would allow that. But there's no real justification for disabling hardware you already own or disabling single player games you already paid for in full.

It'll be interesting to see any test cases that come from these examples.