It justifies it by precedens. Aster means star - astronauts have been called people travelling to stars for a long time, even though interstellar travel is not possible for us yet, so naming their means of transport Starship is not out of line. It just follows a kind of funny naming tradition.
People going to space are called astronauts - in this context I see no problem with Starship.
I’m not sure how the context of the word “astronaut” justifies implying interstellar travel that you aren’t capable of.
It justifies it by precedens. Aster means star - astronauts have been called people travelling to stars for a long time, even though interstellar travel is not possible for us yet, so naming their means of transport Starship is not out of line. It just follows a kind of funny naming tradition.
Is cosmonaut filled with as much hubris?
Depends on interpretation. Cosmos is Greek for the universe
Tbf, they are travelling through the Universe. But so are all of us, so we’re all equally cosmonauts.
Time travelers too
You’re right. I think it could be interpreted as space as well, a kind of universe sensu stricto, excluding our little round home.