It depends how they are designed. Same as regular uranium reactors. Thorium isn’t a reactor fuel after all, it’s what you use to breed more fuel. The actual fuel is still uranium. Thorium turns into uranium-233 then that is the fuel. Normal reactors use uranium-235. Both isotopes can be made to be passively safe.

Literally nothing you just said is correct.

In addition to what has been said already, in many places the cost to upgrade the electrical service to the building to handle the amount of power that could be generated can be as much or more than all the other costs combined. So now the building operators are looking at millions in cost with a potentially 30 year payback period. It just doesn’t make sense at that point.