AIBU to think paternal grandparents are treated as the spare option?

I think men do less to invite their own families over, yes. I suspect this impacts on how often they see their grandkids and how at ease their partner feels with them having the kids. However in lots of cases I personally know, the women don't have family or mothers and would love to be able to rely on any grandparents who would help.

Disagree.

Growing up, my dad’s parents were much more involved and we saw them more often. This was mainly geography - they lived 10 minutes walk away, and so there was lots of popping round, childcare was easier, and they did school pick ups as they were close by. My mum’s parents lived 3-4 miles away - we saw them and had a good relationship but it was more regimented - fixed times on a Sunday for a few hours.

DD sees much more of my parents because they live round the corner. DH’s parents live 40 miles away, so she sees them less and there’s less day to day interaction.

So the main determinant is simply geography / convenience.

Assuming distance is not a factor, it does seem to come down to the son/child’s father.

Many mothers will turn to their own, familiar, mum, for help, and that becomes the norm. It does require the dad to show some interest in maintaining those relationships.

This is my view as an observer, but also as the wife of a man who would avoid family gatherings wherever possible.

That's not how it works for us - both before and since having my son, we've seen far more of my parents in law than my parents, for both practical and emotional reasons.

Totally disagree my parents are great but they live a little further away from us plus are older . My DH’s parents very involved grandparents. They take my son every week for a day and he is just mad about them. I hate to admit it but I think he does prefer them to my parents (even though I obviously prefer my own parents to my in laws).

Unfortunately paternal GPs are worse than spare here, I would love for them to be more involved but they don't bother with us at all. Therefore I have to heavily rely on my parents.

So many variables. PIL are 5 hours away and have had zero interest in DD for well over a decade. I don’t even consider them to be grandparents in anything other than a genetic sense.

Most of the other (local) grandchildren get far more from PIL as paternal grandparents than maternal.

Not here. We probably see paternal grandparents more as they drive so can come and visit for a day whereas my parents need to stay, my parents also don’t have room for us to stay if we visit.

My paternal grandparents were much more involved un my life.
My kids paternal grandparents were basically terrible people so never really had a realstionsip with thier grandchildren, surely it depends on the people involved?