That being said, I wasn't aware of how LIGO changed the understanding of how heavier elements are usually formed, guessing it changed the expected neutron star prevalence? Do you have any additional reading on that?
Regarding the second point have a look at https://www.ligo.org/science/Publication-GW170817Kilonova/in... . That isn't my field of specialization, so I am not sure about recent publications. At the time though this was a big deal as kilonovas seem to be the primary source of heavy nuclei in the universe. That particular event crested between 1/100th to 1/1000th solar masses worth of heavy ( heavier than iron) nuclei. This is a greater rate than supernovas estimations.
It's not about the prevalence, but about the light curves observed during the event AT 2017gfo. They indicate significant heavy metal ejection but, what's interesting, also production.
> mergers of neutron stars contribute to rapid neutron capture (r-process) nucleosynthesis
These two articles cite the relevant papers:
https://en.wikipedia.org/wiki/GW170817#Scientific_importance
https://en.wikipedia.org/wiki/Nucleosynthesis#Neutron_star_c...
Therefore, life could have developed in a few tens to few hundreds of millions of years after the big bang. That's still true even if we assume that heavier elements are created mainly when neutron stars collide and not by super/hypernovas as we theorized before LIGO/Virgo observatories.
Consequently, we likely are not a "progenitor" civilization in the universe if we only consider planets formation. We might not see anyone out there either because there's a great filter for intelligent life to emerge (so the bottleneck is in our past) or because few/no civilizations get to have an impact on their host stars (the filter is in our future) that would allow us to see them.