“This scale” is not realistic in terms of demand or even capability. We may as well talk about mining Sagittarius A* for neutrons.

You don't even need a particularly large scale, it's efficient resource utilization.

Humanity has a finite (and too small) capacity for building solar panels. AI requires lots of power already. So the question is, do you want AI to consume X (where X is a pretty big chunk of the pie), or five times X, from that total supply?

Using less PV is great, but only if the total cost ends up cheaper than installing 5X the capacity as terrestrial PV farms, along with daily smoothing batteries.

SpaceX is only skating to where they predict the cost puck will be.