The thing is that people have a terrible level of patience in regards to long term benefits. For example, people constantly advocate for wind and solar, yet both only last ten years before having to be replaced. And as an alternative, natural gas is often proffered and employed, yet they only last about 20 years before being replaced. Nuclear fission plants have a typical lifespan of 60 years, with even existing plants having a theoretical lifespan of over 100 if the will to continuously refurbishing them exists. As things stand, we actually don’t have a single source of energy as cost efficient as nuclear fission as things stand aside from hydro. It’s just that it also has the single greatest initial investment cost as well, and won’t be paid back during the term of any administration that commissions it, as even in the best case scenario, they take 6 years to build, and can often take more than 10.
I do agree that SMRs are a great next step for nuclear as well as power generation in general, but they are also only a stepping stone. They only last 5 years or so before having to be replaced (as they generally cannot be refueled). But at the same time, we can survive using only stepping stones for the next few decades until a better alternative (aside from full scale fission) rounds the corner. I do hope fusion ends up being that power source, but traditional fission (as well as the newer advances in fission) are still one of the most cost effective, efficient, reliable, and safe. They just have a high political hurdle to face, as people fear what they don’t understand and there is no power source right now that people understand less than nuclear.