Judy and I had our sailboat (previous to our Amel) based in the BVI for 5 years. This was before my full retirement and worked great for us. In that time I got to know the BVI and many of the fine people there, including some government officials. A few of these people are still close friends.
During that time I became aware that one of the world's most porous borders is between the BVI and the USVI. Many boats registered in the USVI would cross into the BVI daily carrying foreign charter customers for a day into the BVI with popular stops at Foxy's and the Bight. A significant number of those boats would not check in with customs and immigration. They flagrantly broke the law. The BVI has really never had sufficient Border Control Vessels so these violators got away with it.
The COVID pandemic has reached the BVI via foreign travelers to the BVI, causing death. The BVI does not have the resources to deal with this and they get almost zero outside help. The citizens of the BVI are outraged at the government's lack of control and almost all of these citizens are aware of the violators on boats from the USVI.
I assume that the BVI government is "sending a message." It is unfortunate that the frequent violators were not caught, but with limited border controls, the BVI caught the first violators they found. When governments anywhere prosecute a violator it is not uncommon that the underlying motivation is to send a message to all of the other violators.
For this reason, I will not send a letter, but respect the reasons that anyone else sends a letter.
It is possible that the government will look at negative letters as a validation of their efforts.