[loudmax]

The fuel cost to launch is significant here, as you'd want to put this into quite a high orbit. You absolutely don't want this stuff in low orbit where it will be taken down eventually by atmospheric drag, or by slamming into some other spacecraft.

Another issue is the reliability of your launch vehicle. Sometimes these things blow up on launch, which you really don't want happening when it's loaded with radioactive waste. Developments made by SpaceX might contribute positively to both of these, by lowering the cost and increasing the reliability.

A third issue is that this stuff might turn out to be valuable after all. Hopefully not for making bombs, but future technology might come up with socially positive uses for material that's currently considered dangerous waste.