We don't only use women's names and female characters or stereotypes this way. That's just not true. Insistence that this sort of thing is always sexist doesn't actually make it sexist. For every Hyancinth or Amanda or Karen or Margot there is a male equivalent if you care to look for it.
'He's turned into such a Victor Meldrew' is the most obvious example that springs to mind. In the 80s if a man was described as a Timothy, we knew it referred to the spineless middle aged man who still lived with his domineering mother from the sitcom Sorry!
There are plenty of others. Being described as a Scrooge, a David Brent type, a Walter Mitty character, Macchiavellian, Little Hitler, jumped up little Napolean, Short Man Syndrome, Mummy's Boy, Grumpy Old Man, White Van Man, Wide Boy, Barrow Boy, Lager Lout, Entitled Old Etonian, Second-hand Car Salesman, or the insult of all insults to describe men who behave a certain way 'he must have a very small dick.'
All those less than complimentary descriptors rely heavily on the negative stereotyping of certain types of men or male characteristics, which have become well-worn tropes. If Amanda is misogynist then these are all misandrist, surely.