Not assuming anything.... But I literally know zero people over the age of 70 who can actually use a computer. Maybe a 70+ or "Greatest Generation" option.
Don't judge everyone by yourself by friend. I am pushing 76, and I bet I am not alone. I use a computer every day as well as a laptop with manuals on CD's in the shop. I also do 90% of the repair work on my equipment. Including buying dead tractors and refurbishing them for resale. Live on 4 A and only 10% is pasture that is not used for lawn, garden, buildings areas, etc.
I may not have/want anything to do with a smartphone but that don't mean I or anyone else in this age bracket can't do anything any more.