It's true that there's always risk involved. As we know, that is true for nuclear as much as any other energy technology.

My view on this is that we are not particularly far away from this being viable even with 2020 technology. And that this is especially true if we are creative in how we apply technology, for example by decentralising the grid and installing storage capacity in people's homes, and by being aggressive with load shifting to reduce the storage capacity required. And there are dozens of promising new energy storage technologies. It seems unlikely that none of them pan out. I thus consider the risk of going all-in on renewables fairly low.

Sure, but the stakes are human existence on the planet. I don't know why you would turn away from solutions we already have with boundable risk.

Because I consider the renewables solution to have comparably bounded risk.

It's still not clear what basis you're bounding that risk on—it seems like optimism that one of the investments would pay off. I would strongly prefer pessimism in this case!