In my opinion this is the strongest argument to take. Any argument about radiation or waste is going to be waved away as "scaremongering" and will be solved by innovations riiight aroung the corner - you won't change anyone's mind with that.
On the other hand, the practical arguments are pretty cut-and-dry: the West is unable to build them fast enough to matter, and they are too expensive to compete with renewables on an open energy market. We already have the receipts for traditional reactors due to Olkiluoto 3, Hinkley Point C, and Flamanville 3.
Have we solved every single potential problem which needs solving for a 100% renewable grid? No, but we've got plenty of time to work out the edge cases during the transition. Perhaps some magical mass-produced micro nuclear peaker plants will help in that, perhaps they won't. Let's keep investing in tried-and-tested technology like solar, wind, hydro, and battery storage until the nuclear folks get their act together - no need to bet our entire future on a nuclear miracle which probably isn't going to happen anyways.