I was curious about your point that we only have ~20 years supply. The article you linked doesn’t really defend that estimate, I think it’s actually pointing out that’s the absolute floor of our supply.
It mentions estimates of undiscovered uranium and also multiple pathways to extend that estimate if there was demand to improve the technology or increase our supply. It sounds like realistically we could find the material for powering all of our energy using fission if we had the demand to do so.