This is what SpaceX has been doing with other unexpected payloads, such as OneWeb. Starlink has a flexibility that SpaceX has taken advantage of to good effect in supporting its other customers. The ability to turn around a Falcon 9 booster is also important in this flexibility. Traditional launch companies have not had this same flexibility, and they relied upon delays of one customer in order to support an accelerated schedule from another. With Starlink, the induced delay is relatively minor, when it even exists at all.

Reusability has been advantageous in so many ways more than just the ability to reduce launch prices.

However, are we hearing any talk about using a Dragon as an option? Somehow I doubt that the Russians are willing to spend the money. (Maybe their next crew can go up on trampolines or broomsticks, or is that being unfair to Yury Borisov, the current Roscosmos chief? It was Rogozin who had made those suggestions for NASA.)

Additionally, another Dragon Crew could be launched by SpaceX. They do have 4 of them, that they reuse, and finding a booster ought not be a problem, considering SpaceX is launching every 6 days or so on average, so shuffling a Starlink mission for this seems like it ought to be straightforward enough. And since it would launch unmanned, it probably does not matter if they a booster on its 14th flight. :) Might feel different with people on board.

The bigger problem with Dragon is there are only 2 docking ports (also 2 berthing ports that Cygnus and older Dragon Cargo use) and this would tie up the second port, and keep additional Dragon Cargo untiul it left. Seems like they could use a few more docking ports on the US side.

The capsules do hold pressure and are used to return experiments intact.

I am sure the capsule could be sent on a less than 12 hour return and I bet a standard suit could keep someone alive for that long.