Earlier quoted context omitted.
I wonder if people really would ossify after hundreds of years or eventually learn to be hyper-adaptable. Current centenarians are a bad example, because their brains and bodies are falling apart. Some sci fi suggests that the fact of our living and dying in just one century means we die as immature children. Maybe it takes a thousand years or ten thousand years to “know thyself” to any useful degree.
In a rather unpopular opinion, I think most people are more of a product of their environments than we like to believe. If you look at the rate at which social change happens and public opinion about certain topics, it happens much faster than new generations replace the old. A good example of this is with same-sex marriage. Opinion changed rapidly and I'm sure many have even forgot all the things said before Obergef…
Do you live on one of the US coasts? Because if so, you are probably right - before Obergefell, most people didn't care about your private life and after Obergefell it could all finally be out in the open. But in a big chunk of this country, it really doesn't matter what the courts decided because there is major political and religious pressure that says that ain't ok. Don't pretend for a moment that a wide swath of states wouldn't send us straight back to 1863 if they could.