POD necessary? Hm. At the minimum no Cuban missile crisis, no Vietnam, no Six Days' War, no Prague Spring- you need a less than bi- polar cold war, you need some factor to stop the superpowers engaging in proxy wars and continuing to challenge each other directly on the high frontier.
Given the enormous- nigh incalculable- costs of direct conflict, as long as both sides had sane leadership it was never going to end in kaboom; considering intelligence, propaganda and disinformation efforts on both sides, they were both trying to make it end politically- first side to have the people lose confidence in the government, or first government to lose confidence in itself, loses the Cold War.
Prestige was such an important tool- again, I think you need both superpowers to have open flanks; someone who can expose, be offended by, and do something effectual about both sides' habit of using third world countries as pawns, to their almost invariable great misery and distress. If the UN actually had teeth, maybe. A multipolar world, maybe.
Give them no choice but to confront directly with open, direct war basically suicidal, make earthbound conflicts harder to get away with, and national achievement the measure, and you might see a lot more happening in space. Somehow blunder into war despite that, and there you go.
Now what sort of space program and presence you have under those conditions, may easily differ drastically- and don't forget some of those projects like ROMBUS were wibblingly bonkers- then you, actually some of those cancellations made perfect sense from the "let's not all explode" point of view, because they included systems that would have been phenomenally destabilising.
Things that were designed to be used in nuclear surprise attack and decapitation, like the Soviet fractional- orbital bombardment system and the American Dyna- Soar. No- one in a multipolar world would have let them fly. No- one in our bipolar world did.
They would spawn a situation where both sides could have reason to believe they could actually win a nuclear war- if they get their shots off first. This is not a happy situation, or a stable one.