The whole point of colonization is to find a 1G Earth like planet where we can live in a normal biological forms and not suffer low gravity or weird planet syndrome or long term radiation.

We don't need more places to live really. The Earth won't run out of resources or get filled up by out of control population and copying the human brain to a machine which lets us live almost anywhere is probably MUCH easier than traveling between stars.

We don't be sending living humans that age like you thinking, we will send tiny probes and beam humans as data and we will do it because we can, not because we have to.