Russia Ukraine war, page-198132

The grain ships just sail inside the territorial waters of neighbouring countries, russia could not blockade without violating NATO waters.

The later vulnerability to SCALP/Storm shadow and to a lesser extent the sea drones caused fleet relocation. Any 20th century style navy would be in trouble with modern weapon evolution, drone swarms and hypersonic missiles id rather be in the bunker with 300 officers than in a big target on the cold water.