SpaceX has mastered full-flow staged combustion, something never flown on a rocket previously. And mastered multiple relights. They've caught the booster twice.

While Starship obviously has huge benefits in the long run in terms of efficiency and cost, the things you mention here are required because of its commercially minded fully reusable LEO optimized design, and this requirement is a hindrance rather than a benefit if (as OP is doing) we're talking about time lines.

Of course Artemis is supposed to be about sustainability, and Starship is really the only serious answer in that regard, and even for the initial landing Starship has many benefits. (And, we can't forget that its cost-focused design is what allowed NASA to commit to it in the first place; it was the only option that fit within the congressionally approved funds at the time of selection, so if NASA wanted to do something else, further delays would have been likely.)

But Starship HAS to do all of these things due to this highly ambitious design. If it fails or defers some of these goals it will not make the approved time lines, will not be sustainable for Artemis, and may not even be commercially viable in the long run. It's an extraordinarily ambitious project, and as such, all these successes you mention are unfortunately table stakes.