Completely agree with a lot of what you have said. I think the boomer generation, which makes up a lot of the grandparents currently being referred to, are being quite short sighted about the support they were given by their own parents, and their longer term relationships with their grandchildren.
I don't think anyone that doesn't actively want to should be expected to or tied in to regular childcare. Whether full time for pre school age or school pick ups. If a flexible arrangement can be sorted, that would be great for both sides but this can obviously be difficult to find ad hoc care if the grandparents what to go away or something, unless there are multiple grandparents able to cover each other. Full time can also be a lot for someone of an older age, and it is more common that grandparents are older now more people are having children older.
The hope of help is much greater now because of the cost of living crisis, so some awareness of this would also be nice. When I was a child it was possible to live reasonably comfortably with a single income of a middle managers salary. Now two full time incomes are needed, with a large chunk being used to pay for childcare. Mortgages/rent, food and bills take up a much larger chunk of take home income, so saving some money on childcare would help most families a lot.
However, a lot seem unwilling to look after their grandchildren alone at all. No ad hoc days, taking them for a few days in school holidays, covering the odd school closure, babysitting occasionally to allow the parents a little time alone. I include my own parents in this (my in laws try and would do more if they lived closer).
It will definitely affect their relationships with these grandchildren moving forwards. They won't be as close as they won't have spent the same quality time together as I did with my grandparents. Time away from the parents when you really get to know each other better. It is a time and energy investment that I would hope them to see a positive return from. Obviously not guaranteed, some of the grandchildren will be a**holes. I really hope they don't regret not taking the time now to start developing those relationships for the future.