I agree that the US government has always had the the right to root through personal communications and possessions if a judge granted these powers. Too often this has been abused but it has also been done properly.
Legally I disagree with the FBI that this is a one time request. If Apple complies then a precident has been set. There will be more requests and we will probably see demands by other law enforcement agencies and by foreign governments, some which will use this information to persecute political dissenters.
Any security weakness deliberately introduced will be exploited by hackers. In other words, putting in a back door or any other security weakness will make our devices more vulnerable to bad actors.
If my computers and phones and tablets must have weakened security to appease governments it is time to give up on digital banking, ordering goods on the internet or securing any information on our digital devices. These devices will simply be too vulnerable to bad actors. As if I don’t have to worry about the current state of digital security.