I've seen accusations of planned Russian expansionist policies based on actions regarding the Ukraine. I've also seen reports on resource scarcities within Russia. Encouraging many kids might lend credence to planning attempts to recapture more of the old Soviet Union, given those two things. But, it's one indicator only.

Better analysts than I will need to look at all the indicators and try to predict what he'll do. I don't see Putin as a 'Crazy Eddie'. That's a specific indicator of someone who out of nowhere will turn do an unexpected behavior for no apparent reason, from Left Hand of Darkness. There's a Russian version from The Hunt For Red October, or earlier, 'Crazy Ivan'.

I think Putin is motivated by some combination of nationalism and greed, possibly in equal measure. In some ways this makes him less dangerous (we can predict), others more (greed can make people do horrible things).

I'm sure the Russian government will provide financial incentives and/or resources to help those whom can't easily afford to raise 8 kids, right?