See the Uber/Deliveroo idea for food. Surely not all elderly have no one? It certainly beats them mingling in supermarkets and cafes picking up infection.
No Uber/Deliveroo for my mum or my inlaws. I'm an only child and I live 2 hours away from my mum. All her neighbours are over 70. We live 1 and half hours away from my inlaws and whilst dh has siblings, we are the closest by quite a bit.
I think there is also a huge difference between a couple and someone on their own. My inlaws would be fine. Massive garden, lots of little projects, each other to talk too. Frustrated sure and would miss their grandkids but I think they'd cope. My mum would be on her own already with mental health issues.