As someone who was born a woman I related a lot to OPs statement “little things like how a good chunk of the online resources are written as if Mum is reading exclusively”.

I have experienced this. As just one example, I grew up playing video games, and back then I often got this feeling as though video games were written as if a boy must be playing them exclusively rather than a girl.

Therefore, I think I agree broadly with what you’re saying, but how you’ve put this point forward is really dismissive of OPs experiences. I’m not sure if that’s what you intended but judging by the downvotes it seems many other people read it this way as well.

Unfortunately I cannot provide any advice for OP directly as I do not have any children myself, but I can speak as to how his situation is absolutely a feminist issue.

Dads being excluded from babycare and parental support groups is a symptom of patriarchy. This is why many feminists often say “the patriarchy hurts everyone regardless of gender”.

Patriarchal ideology expects certain genders to exhibit certain personality traits, and to fulfil certain roles. If you want to go against these social norms, you will get ostracised. OP is experiencing this as he is going against our patriarchal status quo of women being responsible for childcare.

As feminists, and as a society in general, we should be celebrating and supporting every parent who wants to be involved in raising their children. Fathers especially as they are often excluded from existing support groups.