You can make a difference
Given that SE team does not seem to be interested to address this issue, it looks appropriate to point out that there is a way for concerned users to put their own effort into addressing this issue.
For this, take into account that hot questions listed at sidebar are indeed picked from a larger source list, link to which is provided in sidebar list header. This larger list contains 100 questions that are spread fairly evenly across different sites - in other words, there is no over/under-representation there.