True. That can easily happen. Reason enough to not push that angle, at least not directly. There are other ways of phrasing that.
Besides, for humans, there's no longer such a thing as "being adapted" to the environment, at least not in that limited sense. This is not an Earth versus Mars thing, it's just a matter of latitude.
If natural abilities were such a big factor, we wouldn't need clothes in Norway or Canada to survive in those places, in winter. But we do. Plus heating.
Humans are not "adapted" to live in all environments on Earth, at least not without tools, which includes clothing. So, if your skin is light and you are in an area with high insolation, cover up more and try to spend less time in the sun. Add some sunscreen too. If the skin is darker, do the opposite. Add some supplements as needed. Done. Adapted to the environment.
Of course that's a highly uncharitable representation of what you propose, but you would have to expect that kind of treatment.
However, given the vastly higher death rates among people with darker skin, it should be shouted from the rooftops.
Unfortunately, this would put into question the narrative that anything but systemic racism may be to blame.
Furthermore, pointing out that people with darker skin are not adapted to live up north could easily be misconstrued as an anti-immigration stance.
“Far-right quacks are pushing unproven treatment for COVID” makes for a juicy headline.
So, who wants to be the first to put their reputation on the line?