> Is there any reason to believe that they would have been more generous in giving credit had the work been from a man?

The what-ifs of one specific notable instance doesn't really matter. This is merely being used for illustrative purposes.

It is also the case that it is not just women who are denied credit, but until relatively recently it was common practice to not even think to give equal credit to women.

> And are there not dozens of other researchers who Watson and Crick drew inspiration and results from, who are not listed on the Nobel Prize?

This direct? No. Franklin generated the key bit of information from which anyone generally adept in the discipline of the time could verify the double-helical nature of DNA.

> This is merely being used for illustrative purposes.

Stated more cynically, it's being used to craft a narrative in support of an agenda.

I don't see inductive reasoning used for debate as particularly cynical.

> No. Franklin generated the key bit of information

No. Her student did.

Sure. Under direction from her. This is another problem entirely in the Sciences, and society in general (particularly looking at politics).