Because people still buy them. It's that simple.
For a parent buying for a smaller kid, a business/organization buying for its employees, or a senior citizen who just runs a few apps, it's ok.
It's obviously not for people wanting to record videos in 4K (or record videos in general -- lots of older people only record a few minutes or so a year, some grandchild's birthday or such).
If you do that a lot, you get a higher end model.