The nuclear family is mostly dead. How long will it be before the only ones having kids will be from the LGBTQIA++ community?
It is, but it wasn't the Pride movement that "killed" it.
It's been dying a slow death since the 70's.
Gay & Lesbian couples weren't going to be making babies or raising babies in a 2-parent hetero home either way, regardless of which legal rights that did or didn't acquire (or what kind of flags they wanted to celebrate with) in subsequent decades.
It was the sharp uptick in labor force participation that's the culprit.
While the benefits or issues of the "Dad goes to work, Mom stays home with the kids" dynamic can be discussed at great length, the one thing it did accomplish is keeping the applicant pool smaller, thereby giving the applicant/candidate more leverage in salary negotiation.
(stands to reason, if you're the only applicant, or only up against 1-2 other people for the job, your chances of being able to fetch a higher salary for it are greater than if you're competing against 4-5 people)
Obviously that introduces some challenges and valid discussions to be had about rights, equality, and fairness.
None the less, with that decrease in leverage came lower & stagnating salaries at the lower end of the pay scale, which resulted in it being a situation where most households need two incomes in order to stay afloat (which piles on the childcare costs on top of it)
In essence we went from
"Dad goes off to the widget factory to make widgets and makes $70k, Mom stays home with the kids"
to
"Dad and Mom both go off to the factory to make widgets, each making $40k, and $10k of that goes towards childcare"