They are quite right. Nor should Scotland subsidise energy exported to England.
If England needs our energy to keep its lights on it will pay a price that meets the costs, plus a reasonable commercial profit. If it can buy cheaper elsewhere that is what it will do.
The Scottish Goverment should phase out promptly all subsidies to offshore wind.
It will then be a straight commercial decision how many more offshore turbines to build. The energy companies operate on both sides of the Border, both in generation and in distribution, and are best placed to make these commercial decisions.
Given the huge price guaranteed by the UK Government to get a new nuclear plant started, there would seem to be a good prospect of demand for Scottish energy at a profitable price.