> Lots of people didn't think that segregation would ever end, nor that humans would walk on the Moon, nor expected the Soviet Union to fall... yet they did, surprising a hell of a lot of people by how quickly it happened too.
It's an important point.
The US rapidly legalized gay marriage at the federal level once serious momentum had begun. That's despite only modestly above half of the nation strongly supporting it at the time (according to polls anyway). There has been no war over it, no great social rebellion, no states attempting to leave the union, no mass acts of anti-gay terrorism over it, no religious revolt. Trump had zero political interest in attempting to turn it back, there was nothing to gain from that because there isn't much support for rolling it back. Not much happened at all overall, there have been very few negative events related to it culturally. Only a few years prior to that legalization, the liberal President was still publicly against gay marriage on the campaign trail.
Obama changed his position to supporting gay marriage in 2012, shortly after Biden did. Gay marriage was then legalized in 2015. It was nearly unthinkable that that was going to happen as recently as the 2004-2008 political timeframe. In ten years it went from only half of Democrats supporting gay marriage (2005 per Gallup), to being legalized nationally.
It's always worth considering how many people answer as they do on polls because they're afraid to be openly out of majority alignment, yet they may support a position quietly or otherwise not oppose it (meaning they'd never actually pose any cultural resistance to change). That's exactly what the case was with marijuana legalization; serious opposition to legalization was never as great as it was portrayed to be. And that may also end up being the case with psychedelics, perhaps with more regulations (I'd expect the public to be more leery than with marijuana).