I agree that it has been a generational thing. It was called the "Me Generation." Me, me, me. In the animal kingdom, parents abandoning their children to be completely independent is mostly common among insects, lizards, and amphibians, and is associated with large litters and a massive death rate among them. It's not modern, it's a feature of creatures that are lower than mammals.

What's triggering is the fact that you've decided to brag about your superior parenting in public, and claim the evidence of that is that you have told your children that you're done with them. Nobody asked you, and you're aware that normal people don't do that to people that they are close to (hence the need to lecture.) Everybody raises their children to have the ability to be completely independent and self-sufficient. You just think you're uniquely successful at that, and that it somehow would be the child's fault if you've failed.

Your kids didn't ask to be born, and if you don't rescue them from their failure (at least initially), it will be a reflection on you. If we are in the same social circles, and I know about this, I will judge you. Even hearing you explain it, and your feigned confusion (I guarantee you have this conversation all the time), would make me wary of hiring you into a management position.

I'm not a lizard. I want everybody I care about to be self-sufficient, and I also don't want them to try to be unless they actually have to be. They have resources available to them that are not always being fully utilized, and when those resources can give them an advantage in any context, I would be angry if they weren't used.

There are always limits to self-sufficiency, because there are massive advantages to abandoning it: that's what we call civilization.