Except some of them are still building new plants today (large ones cause higher efficiency, unsurprisingly). For China and Russia those are entirely separate from the kind of reactors used for plutonium reprocessing or medical isotopes or whatever else, they only exist to boil water at the end of the day. The only incentive here is electricity, and both have plenty of other options available.

Bit of a paradox isn't it? They'd just burn coal or gas instead if that was much cheaper.