You're missing the point that it takes only one sufficiently equipped human being to set the whole colonization in motion. Given appropriate technology, it does

You're missing the point that it takes only one sufficiently equipped human being to set the whole colonization in motion. Given appropriate technology, it doesn't require any concerted effort or grand scheme. Just a single match lights the fire. Think of the DIY folks in 500 years. Given the size of the human population, it's a given that it will happen at some point, if the technology becomes available.