It’s sign of how desperate they are getting to be publicly shopping such shit ideas. How the fuck would that even work? Sure, they can board Russian flagged merchantmen and risk a naval confrontation they bet they can win, but Russian flagged ships will only be carrying a tiny fraction of all sea based trade to and from Russia. They are going to stop Chinese and Indian merchantmen in international waters as well? Not even the Euros would be on board with such a craptastic hairbrained nonsense.
The Russian economy is primarily based on real resources and manufacturing. That means they still have real tangible assets they can sell, and worst case, barter for trade, so long as they got the factory of the world at their backs ready to supply them with almost anything they need.
That puts a hard bottom on how bad things can go for Russia, and to be frank, they are not far from that already. But that also means the current western sanctions are about as damaging as they every will. Why else would they literally be sanctioning Russian cats and dogs if they had anything left of any worth to throw?
In contrast, American and most western ‘advanced’ economies’ economic might are based overwhelmingly on intangible make believe promises, which are all too often promises of future benefits to boot. When trust breaks down and everyone starts calling in their chits, all hell is going to break loose when people start to realise the actual real world realisable value of their net worth is going to be a tiny tiny percentage of what their bank/portfolio statements says. That means there is no bottom for how bad the economics downturn could be in the west if things really go south. and that’s why they are running scared. The Russians can outlast them.