But are you concerned with border agents searching your phone? If you are then any time spent on this is time well spent. Although protecting your password manager is obviously of vital importance, there's a lot more to be concerned about sitting around on your phone if they can get in.
There's also the general concern -- although I don't know if it's ever been proven to have happened anywhere -- of border agents installing tracking software / malware. They often take the phone out of sight for a while. This is probably more of an issue with Android phones but again if you are a journalist or human rights activist or anyone with legitimate reasons to be concerned, I would absolutely want to wipe the phone as soon as possible after a border crossing if agents had forced me to hand it over for inspection.
There's also the general concern -- although I don't know if it's ever been proven to have happened anywhere -- of border agents installing tracking software / malware. They often take the phone out of sight for a while. This is probably more of an issue with Android phones but again if you are a journalist or human rights activist or anyone with legitimate reasons to be concerned, I would absolutely want to wipe the phone as soon as possible after a border crossing if agents had forced me to hand it over for inspection.