But whatever the UK government does on coronavirus is irrelevant to Scotland since it has its own government that can do what it thinks is the right thing (with the exception of closing the border to England). If it's going badly for you in Scotland, it's Sturgeon's fault, not Johnson's.
It (Coronavirus) isn't going to go well for anyone of course, but I'd say that Nicola Sturgeon shows more leadership and competence attributes in dealing with this crisis than does Boris Johnson, and his crass remark the other day is just one example of his comparative failings.
Moreover, there is still the Brexit issue in the background, which is primarily a Tory-driven policy and the key issue that saw the Tories elected, so if anything the performance of Boris Johnson is crucial. For example, should the Coronavirus issue be one that lasts for a good chunk of the rest of this calendar year, as seems likely, is Johnson still aiming for a no-deal scenario in December or not, and why is he not already addressing this aspect.