If I want to copy some information on my iPhone and use CMD + C for it I can paste it with CMD + V after restart. After I turn my iPhone off and on again.
For example I have typed in Safari Browser:
I mark this two words and use CMD + C.
I restart my iPhone. Open Safari, use CMD + V and get:
With MacBook Pro the stored information cannot be accessed after restart.
Maybe its some rules, that the information on mobile version of Apple OS is stored und for "normal" OS, that is used on Apple Notebooks and Desktops is deleted after restart?