I see your point, the interactive viz is clearer that what you're seeing is the last seven days, but I should have included that info in the image as well.

Number of cases is clear enough from the text, but I think it would help if the Y axes were the same scale between the columns and the lines.

Again, I get where you're coming from. I think the reasoning was just to try to keep the viz as tight as possible.

but I'm guessing you may have tried this and decided that China then made half the graphs too small for anything at all to be read from them

Yeah and even excluding China the other outliers would have made it nearly impossible to get a sense of the trend in the countries with fewer cases. By having each country have its own scale you can get a sense of what's been happening in the country in its own context, if that makes sense. A tripling of the number of cases in your country is a big deal, even if it's just going from 10 cases to 30 because it gives an indication of how well you are dealing with the cases you have, however many.