I think it depends on politics. We live in a capitalist statist society, if people were free to CTB then capitalism would lose quite a lot of consumers and workers since ironically, capitalism causes or at least exacerbates a lot of people's suicidality. If we eliminate capitalism and replace it with a system that doesn't revolve around making life great for 1% of people then I imagine it would be a lot easier to get assisted suicide to become universal so long as religion no longer has an influence on societal rules/regulations/laws. I also think outlook on children would affect age limits and what not, I think if we hold the same view of people under a certain age (could be 18, 21 specific number doesn't matter) not being able to make that choice then it'll only be universal for people above said age whilst people under that age may have to fit certain requirements or just flat out have to continue suffering until society deems them capable of deciding their suffering is enough. I think our view of children in relation to their parents also would influence how fine we are with it, since we currently view children like the property of parents, there would be a lot of opposition to people of all ages who still have live parents being able to CTB on the basis that you're "just cowardly spreading your pain to others/wasting the hard work of your parents". I also think when climate change starts to really hit the fan CTB will become a lot more acceptable because maybe for once pro-lifers will truly accept the fact that if you're gonna die anyways might as well die on your own terms rather than go through a period of climate catastrophe never before seen in human history and CTB may even be implicitly encouraged because it decreases the amount of people needing food, shelter etc. when climate change disrupts supply chains and destroys a lot of buildings and homes so it would be more convenient if people CTBed, unlike nowadays where people CTBing inconviences the locals through the mental pain it causes and inconviences the government because that's another worker/taxpayer/potential-conscript gone. I believe climate change will at least temporarily cause a pro-CTB shift, though that shift won't be pro-choice but outright encouragement for convenience, after climate change who knows, human society will surely change so much once climate change ends our current ways of living and systems it's borderline impossible to make any predictions that far ahead.