Not for anyone who has a basic understanding of geopolitics. Do you want rogue nations hoarding resources? Do you want Superpowers to act as the British Empire did and enslave entire nations and exploit them at the point of a gun? The massive zerg rush to resources would instantly cause a world war. Right now you have a system where the world trades for goods and everyone profits that is a part of that trade. Take that away and you have trouble.
I’m not sure if you’re aware of this, but it is possible to want part of the game to work differently without also wanting the complete collapse of the game proper.
The US Navy is the global security provider of free trade on the sea. It is one of their core functions. To 'just go back to our own borders' would be to completely remove the only naval force cable of providing security for free trade on the sea and thus remove huge portions of safe, navigable waters for said trade.
Who else has the navy to make it happen? China's navy has no range, France and England's navies have the range but aren't large enough. Everyone else's navy is too small and can't deploy at range.
We don’t have pirate fleets anymore and any pirate group that obtains a ship big enough to really be a danger would be eradicated as soon as they showed their hand.
With what? Their little dingys are no threat to a cargo ship with a few armed guards. If they somehow get ahold of a real vessel then a national navy can go sink it
The whole idea is to not let things get to that point.
It's also important to recognize, the US withdrawing internationally (and wasting tons of money we've already spent, mind you) doesn't mean places become a harmonious area. Another country will replace it.
Given how much international water China already claims is actually Chinese territory, and their ships harassing and sinking civilian fishing vessels, I would rather stay with the devil i know.