Eh, gallows humor from a random nobody is one thing. Joking about basically ending the world as we know it from someone who literally has the power to end the world as we know it is another.
This faux pas is certainly not at the top of my list of criticisms of Reagan, but he did deserve some shit for it.
Source? The Yale link above specifically mentions:
Anecdotally, I was in a STEM-focused school and major over 20 years ago, and it was overwhelming male-dominated. One of my colleagues graduated less than 10 years ago, and her experience was not dissimilar. She had to deal with quite a bit of sexism too, unfortunately.