Seems there's no mention of Russia in the article, but they seem to have a rich tradition of small reactors[0].

My understanding is there's still ongoing research/commercialization work but the fabled "many and cheap" production state hasn't been reached there either

[0] https://en.wikipedia.org/wiki/List_of_Russian_small_nuclear_...

... cracks .... cracking ... cracked .. cracks..

there's a remarkable similarity to the life of these units.

They worked, until they didn't.

"ah, but we're much wiser now" is of course in this too.