The maximum speed of information and how spread out space is, combined with the likelihood of fully automated planet destroying superweapons that can’t be well defended against being the meta for future warfare, make this a very bad idea IMO. One of thousands of humanity’s offshoots goes nuts and decides we all need to die, it’s over, and you’re rolling the dice with every one. It is clear that on a population scale we do not now have our shit together enough to keep that from happening even with the benefit of instant communication, let alone without it.

Creating human colonies throughout the galaxy at this point would be like making copies of a severely mentally ill and suicidal person in the hopes that the clones will have a better survival rate if there’s more of them. It is stupid. Human culture and organizational technology need to be way better before we even consider spreading out into space because otherwise we’re facing the exact same apocalypse just on a grander scale and harder to resolve. Probably shouldn’t even send humans, instead craft some artificial lifeform using us as a template that is inherently better at this stuff than we are.