Child of the 70s here. This generation of GP is different. My parents have passed, sadly, but my MIL retired at 50 (big civil service and teacher pensions) and FIL retired at 62 on another amazing defined benefit pension. They are in full health, relatively wealthy for pensioners, have nothing to do except take luxury holidays and get their entire house and garden professionally renovated every few years. I absolutely love them, and we try not to take advantage of them but they do love looking after our dc in the holidays and taking them for day trips and whatnot.
Contrast my own GP. They didn’t retire on big pensions in full health. Remember that few people in the past would have enjoyed a long and happy retirement.
My Grandad had been badly injured by gas and battle in WW2 and needed permanent care by my poor old gran who had had to run the family shop to keep them afloat in the post-war years. He died when I was small and anyway men of that era didn’t do childcare, so of course no question of him helping out.
By the time grandad died, myGran was knackered out and whilst she adored me and my db, it was very much a case of my mum going to look after her in her 60s onwards, no question of my gran ever babysitting.
Even if my gran had been energetic enough, Gran couldn’t drive, that’s one problem common to the working class women of her generation. She lived in the next town over so it would’ve been a bus ride to come and help in an emergency.
So - yes, my relationship with my gran did consist of gathering wildflowers for my grandad’s grave, making jam, baking cakes and making crafty things from leftover wool and Christmas wrapping paper. But I don't romanticise that like you do. My gran couldn’t and wouldn’t do more - she was a stubborn old battle axe who had lived an astonishingly hard life. Her reward was her unfaltering faith in God and a hope that I would grow up and get a good education and live in peace, which thankfully I have.
I don’t judge GP for wanting to forego the dubious pleasures of being very involved in the lives of the GC, I also don’t compare them to irrelevant circumstances of 40 years ago.