This is all so theoretical though, and many decades in the future in the best case scenario. Someone with your opinions arguing about this in the 1970s would'v

This is all so theoretical though, and many decades in the future in the best case scenario. Someone with your opinions arguing about this in the 1970s would've argued we'd have had all this long before now, yet we don't. It's not clear that any progress will actually be made in the coming decades either; no one is seriously working on it like SpaceX and Blue Origin are working on their Mars rockets. Chemical rockets have had thousands of successful missions. NTRs not only have zero, they don't even have a single complete rocket that's ever been built. If you want to get to Mars any time soon, don't pin your hopes on NTRs. The people who are actually doing the thing certainly aren't.