The first thing to consider is that this thing won’t be stationary!
Geosynchronous orbit is much more expensive to reach per kg launched, even for Starship… when it starts working properly.
Lower orbits… aren’t stationary. Who wants a data centre that’s “over the horizon” from the owning country most of the time!?
If you think AWS egress costs are bad? Just add some zeroes! No, more zeroes than that…