Tails and purism phones are the same 'I run qubes' fantasy that I expressly ignored. No one uses these, and they are not going to ever use those systems. There are fewer 0-days and CVEs in the mobile environment and for at least the next five years or so the mobile environment will always be more secure than desktops. Right now the single biggest step any 'normal' person can take to secure their digital life is to throw out their desktop and live completely on mobile devices and consoles for gaming.
Unless you're buying a new flagship every 2 years you're probably not meaningfully more secure than you would be on a desktop. And buying a new flagship every two years is probably less realistic for most people than running purism or Tails. Those at least only will cost you time.
