If a society was sufficiently advanced that they could just press a button and make a star ship at will, then they would probably be equally advanced in other areas and would not have any need for star ships.
That's a non sequitur. A society advances on numerous axis, but doesn't necessarily advance at the same time. Society can be immoral and enough scientifically advanced to have such machines. I'm pretty sure Romulans in that universe had replicators and they were known for their black ops division.
Good point. Though I think that the suggestion was that the technology required to materialise a massive, warp capable star ship may be more advanced than a different technology that accomplishes the same tasks as a star ship. For example being able to teleport both people and nuclear weapons across the whole universe would pretty much render star ships obsolete.
Maybe people are just too romantic and nostalgic to realize their wildest dreams with holo decks, telepresence, brain implants and let AIs decide on their well being. Maybe instead of spawning self-replicating robots for space exploration they want to do it physically themselves like their ancestors explored the continents a long time ago.
