To build on the economic/practical issues.

The useful life of cutting edge AI server hardware will require constant rotation of equipment to potentially remain competitive with more accessible solutions.

Heat management ( https://m.youtube.com/watch?v=-w6G7VEwNq0 )

Hardening of equipment for the environment. ECC isn't going to be enough. I would have to defer to experts about the best way to manage it, but it either means custom hardware, weight, or both.

Repairs are impossible. Hopefully a sat can degrade gracefully, but routine repairs on earth become significant outages/decreases in economic value of a sat over time.

Rocket launches have gotten much better, but are not perfect. Insurance is a thing. However, cost of equipment in a failed launch may be eye watering, rivaling a governmental military launch.

To give a datacenter in space constant exposure to sunlight, the orbit must be either very var away, or occasionally be on the other side of the earth from you. Either way, the latency is terrible. You can put them in a ring and only choose the one closest to you, but are you really going to keep moving your data from satellite to satellite? So, bad for interactive use, maybe OK for non-interactive use, if you can afford the 30 foot by 30 foot solar panel and a similar size radiator for an 8x B300. That will be about $15M for your $500K GPU set. Plus $7M for the launch at SpaceX public rates.