Just FYI, men do go through hormonal changes upon becoming fathers, as well as changes in the brain:
www.nytimes.com/2020/04/15/parenting/baby/fatherhood-mens-bodies.html
This appears to be linked to how much care they provide for their babies. It’s not a massive stretch to consider some outliers might have their endocrine systems go haywire, and require some additional support from mental health services.
I have no idea how common this as it’s not a particularly well explored area of research, but it is scientifically inaccurate to say men have zero hormonal responses to fatherhood, and when hormones are in operation there is always the chance of them functioning incorrectly.
If the nomenclature is a problem, and I agree it’s probably a mistake to conflate it with PND, as we have different hormones operating differently, just call it post paternal depression or something.
Some of the responses teeter dangerously close to expecting men to just man up when they are struggling, which is a pretty big contributor to the toxic masculinity we would all benefit from being well rid of.
I know all too well how devastating PND can be, I had a female friend I visited in a special psychiatric maternity ward, so I am in no way claiming parity here, but I think it would be very unwise to attempt to brush this under the carpet, it should at the very least spark scientific/medical curiosity and certainly not outright derision.