I’d actually guess this is a bluff move to convince countries that a confrontation with Russia would be too potentially damaging - in the hopes that NATO would back down. It seems really bizarre to push specifically against Estonia though - rather than Norway/Sweden (Arctic Sea claims or Gotland) since Estonia has a high enlistment rate and is openly keeping force on the table in opposition to Russia - Norway and Sweden are much richer economies that would be more likely to give ground if pressured due to the high predicted economic damage.

Not to mention the Russians will have 40 million ukranians to expend on the front line and /or work to death. Plus the Ukranian war industry is pretty impressive, even on global scale.

My guess is that Russia is trying to create a threat to NATO countries so that those countries will want to hold onto their defense materials and weapons instead of those going to Ukraine.

NATO is not exactly strapped for materiel at the moment, especially if considering quality vs. quantity. Given the way that an Israeli F35 was able to operate with impunity a short while ago, I don’t think the old Soviet gear would fare too well. https://theaviationgeekclub.com/iriaf-commander-reportedly-fired-after-he-kept-secret-that-israeli-f-35-stealth-fighters-had-violated-iran-airspace/

Or Putin is trusting that Nato will hold the baltic countries back and he’ll be able to do what he wants to them, provided no invasion.

The European NATO members did continue supplying Ukraine. However, the US had previously accounted for roughly half of the total arms supplied and Europe didn’t do anything extra to make up for that sudden colossal shortfall.