Unexamined cultural programming.
Back in the late 90s when the first possibility of same-sex marriage equality started glow to life, many mainstream LGBT activists were skeptical at best
We didn’t WANT it. It wasn’t any part of a planned Equality strategy. Emulating millenia of programming and unexamined behavior didn’t appeal to people who’d just spent the last decades fighting for the right to be different and to create our own ways of being.
We thought we could create BETTER models and institutions.
Well, that didn’t work out so well. The grass roots roared, often (quite naturally) motivated by being told they weren’t allowed to have something.
So LGBTQ activism became for many people a fight to emulate straight/cis society at large.
I don’t suggest there’s anything wrong with people living the way they want to live. If monogamous marriage and 1.2 kids is what some LGB people want, then yay, I’m happy if they’re happy.
But I dunno. I think the plunge into marriage equality distracted lots of us from really examining ourselves and the values we take for granted - without ever stopping to think about them.