I do hope some of the elderly are already self isolating or at least cutting down contact and not waiting for the government to force them.
Part of the issue is that none of the 70 to 80 cohort I know consider themselves elderly. My maternal Grandmother lived almost another 30 years from her 70th birthday (the other one made 25 more years) and my mum is more active at 76 than many of my friends because she needs to be for her mental health. She's also currently 400 miles away from home at the moment.
On dh's side, his parents are very much aware they don't necessarily have much time left and don't want to waste any of it. MiL is from NI and has anti authoritarian streak a mile wide.
When I discussed self isolation/no medical care with my mum her reply went something like "we're all going to die at some point" and a reminder that coronavirus could leave me and dh very rich (inheritances from her, dh's parents and my paternal aunt), the subtext of which I presume is stop nagging.
Our village has set up a group for deliveries. So far despite a lot of 80 plus people living here, I'm the only person who has asked for something as we are self isolating due to symptoms/one of dh's colleagues having a friend confirmed as a case. When I was opening the kids curtains this morning, I saw my 98 year old next door neighbour heading off to catch the bus into town...