I’ve been reading the House of M series and it seems pretty well established that this alternative reality is based on Magneto seizing power in 1979. But how did a change at this point affect Captain America? He supposedly was never frozen in this world and is now an old man. But he was frozen in 1945 at the end of WWII - I realize comic book time is flexible but this seems to be impossible to reconcile. Am I missing something?
Well I think its as simple as Cap never getting on that plane that dumped him in the Arctic. Remember, House of M is mostly about the heroes fantasies coming to life so Cap is an old man without the Captain America mantle bearing on him. Also remember this Scarlet Witch has the power to change the past so dont expect House of M to measure up to current Marvel continuity even though it is in continuity. I hope this helps.