Good developments, but we cannot wait for them. Even the coal grids are falling apart now, and building gas to replace them is not sane.
On the other hand, once they're available, switching to them is perfectly fine, and the 50+ lifetime of LWRs exists for a reason. Maybe we will even have workable fusion by then.
It appears the NuScale pilot project is floundering. They announced cost raising about 50% and about a 3 year delay. Several of the utility customers have backed out of the project as a result, putting it on iffy grounds.