For me, it is not the size. Its the pixels. It is fairly easy to get a large monitor these days. It is harder to get 1200 or 1920 pixels across. The only way to get that many pixels without also losing huge amounts of valuable desk surface ( as in where I can put my coffee cup and magazines and other non-electronic stuff ) is to get a laptop.
When will people realize that their reading text may be because it there are not enough pixels to fully render it. Not because it is too small. Making that same paucity of pixels bigger doesn’t really help.