pointless space colony impossibly distant from actual earth

That's the part that really gets me. It's even worse than building a colony on Mars or the moon like Musk wants to do. If by some miracle we ever solve climate change and do falgsc then maybe having outposts and infrastructure throughout the solar system would be useful.

But the rocket in the Civ V science victory is a colony ship headed four light-years away to Alpha Centauri. Most people who left on that ship will be either elderly or dead when it arrives and it'll take 8 years to send a message back to Earth and receive a message back. No significant resources will ever make their way back to Earth from Alpha Centauri and no significant resources will ever reach Alpha Centauri from Earth. In a matter of maybe one or two generations the colony becomes culturally alien to Earth due to lack of meaningful contact.

Now we have people out there living a harsh existence on an alien world just so people back on Earth in whatever nation got the science victory can point to Alpha Centauri and use it to brag to other nations.