You may have found a problem with my idea 🤣
There would be no naval counter to this other than brute force with bombers or rammers and accepting the retaliation damage. But at least there would be consequences to setting up two bombers 3 tiles away from every opponent's port and just sitting there annihilating any ship that docks there.
And these ships would offer no offensive utility, but would be expensive (10-15stars?). They could even have 0 attack.
Pre-update, even with no ships and a battleship blockade, you could make a battleship and it would at least deliver a retaliation shot before dying next turn. You could at least wear down a blockade.
Now, it's just impossible to recover once you have lost control of the water. It doesn't matter how strong your economy is or how elite your land units are.
If you don't have the economy to build them, you would still lose. But if you have an economic advantage over your opponent, this ...