Sounds entirely plausible. I don't know this webpage either, but the tone is not sensationalist, and considering the sexism in all other parts of society, it would be more surprising if women weren't discriminated against after death.
If a doctor isn't able to tell when a woman has a heart attack because he only knows male symptoms, he'll also not be able to tell when she did NOT have a heart attack. Et cetera.
Besides, many women are murdered by their husbands, while the other way round is rare, and of course, the spouse would be the first person to want the death investigated ... IF the spouse wasn't the murderer, that is.
Thus, many men being murdered by other men: Wife stresses to doctor how healthy her husband was and how unlikely a natural death.
Woman being murdered by her husband: Husband tells sob story of illness and long suffering.
Considering just how many women are murdered by husbands (and sometimes by male relatives), it is likely this would turn up in the statistics somewhere.