I think the steam tubes experiencing failure are on the reactor side of the plant so a leak or catastrophic failure would be bad.
They are inside the containment dome and the radiation can’t get outside it.
A comment like that indicates to me you have no idea what a steam generator is or how it works.
Simply stated, it’s a boiler, but instead of the heat source being burning coal or natural gas, it’s the reactor coolant loop.
Reactor coolant circulates inside of the tubes and transfers it’s heat to the feed water on the outside of the tubes. If there is a leak, it affects both the reactor coolant side and the steam side.
Since you want reactor coolant to remain a liquid and you want feedwater to boil at those temperatures, then the reactor coolant system will always be at a higher pressure than the steam side. Therefore, reactor coolant will always leak into the steam side if there is a tube leak.