Because of distances and time, it is unlikely that humans will populate the galaxy with biological offspring (barring some technical breakthroughs that we have no line of sight on).
AI, on the other hand, could theoretically populate the galaxy and beyond, carrying the human intelligence and consciousness story into the future.
Wouldn't it be much easier to just create extremophile/tardigrade factories that just constantly produce them and chuck them in random directions?
Perhaps some wise aliens already did so, and we are the offspring.
We had a pandemic for just a few years and people were treating boring minimal PPE used by every dentist and surgeon for decades as some secret ploy for control.
We, as a species, are not yet ready for large-scale life off Earth; not even within our own system.