re: NASA pushes back dates for Artemis II and Artemis III missions.

The per launch cost numbers for Starship assume something like 140 launches per year which amortizes their manpower cost across those launches. That's a cost of about 2B per year which is more than what we spend on SLS. I'm not saying SLS is cheap but you are comparing apples to televisions.

Plus you are using predicted numbers on extrapolated launch rates, none of which is proven. It's really easy to make up numbers and feed them to the public.

A more accurate cost comparison would be cost per mission. There are plans to bring SLS's costs down. Will it touch what SpaceX can do? Well, probably not, but per-mission costs will be closer than you think when you take into account 20 launches per mission for Starship for Artemis.

Simply launching SLS twice a year would make up that difference.