Yes, if you change a word to draw a false analogy, statements do look ridiculous. I can do this too:

If you are by default an apple, you probably should not be playing the ocarina.

Lifting and tanning are not analogous. They are not even close to the same thing. Your body tans because it's trying to save skin. Your body does not get stronger because it's trying to save muscle fibers. The skin saved by tanning will die faster, it just doesn't die as fast because it's tanned. Your muscle fibers don't die faster from lifting.

This is a false analogy. It's not a legitimate argument. They are similar in that they involve stressors, but that's only a superficial similarity.

far more lives worldwide are lost to diseases caused by lack of sunlight than to those caused by too much

Yes, would you look at that -- a statement which is, if you read what I'm saying closely, not at all in disagreement with anything I've said.

Many people with dark skin that is an adaptation to high amounts of sun now live in areas with very low levels of sun. People with skin adapted to low amounts of sun can live in places with high amounts of sun and simply not go outside as much, but people with skin adapted to high amounts of sun living in areas with low amounts of sun have no means of exposing their body to more sun if the environment doesn't provide them with enough sun.

This would, for the 3rd or 4th time, also not indicate that sun exposure sufficient to tan is in any way equivalent to sun exposure necessary to provide the body with adequate vitamin D.

The most charitable reading of your reply would be that you're trying to draw some very general and simplified conclusion like "sun exposure = good" and this is a really stupid thing to try to do.