Russia is very limited in the Black Sea and can’t bring anything in without a major confrontation with Turkey.
This ship was being used as an alternate method to deliver war supplies to Crimea as the land routes are increasingly under threat. So, while by no means a “decisive blow”, it is significant. I’d have to agree with you on “tactical blow”.
Understood. The key here is to keep things from being blown out of proportion, IMO. Losing the ship is a blow, but it certainly won’t end the war