Re: Had a recent train trip myself
"Everybody seems to have to fumble around for a couple of minutes to pull up a screen with the code if not longer."
That would be the same people who manage to bury their paper/cardboard ticket in the bottom of a bag or forget which the many, many pockets they put in and wait until asked before they start looking.
It's not hard to be prepared to show your ticket when asked and actually be ready. Unless you happen to be right at the end of the carriage the inspector is starting from.