Increasingly, it seems like Starship is not 'a' approach for colonizing Mars this century, but it is 'the' approach. I speculate that if there was no SpaceX, the national agencies or one of the sluggish aerospace companies would eventually converge upon the same design after many decades. Then you think how the only reason you have a commercial crew program at all is a series of NASA decisions that resulted in having to abandon the shuttle for basically being a 'jack of all trades master of none'. And you also realize how incredibly unlikely that SpaceX became as big as it is today, being extremely close to failure at many points. Then came Trump and Jim and many other unlikely things that accelerated space exploration like NASA being cornered into choosing Starship for Artemis. People complain about how manned spaced exploration slowed to a halt after Apollo, but it seems as though history conspired to create Elon and SpaceX and to let us reach Mars as early as possible.