This is a bunch of alarmist nonsense. For starters this is no "backdoor" it's front and center, and the author acts as if the concept of locking a user profile behind a password on the OS level is a completely foreign one.
Client side software devs assume that a user set up a local password because there is only so much that can be done for the user, and otherwise this makes this sort of software very cumbersome to use on a continuous bases.
I wasn't concerned for this exact reason. I have a secure desktop password and take adequate precautions to ensure security.
The only real risk is with work computers, and anyone who doesn't have their desktop go to screensaver with password unlock after 5-15 minutes activity is just an idiot.
When I was in the bank getting my mortgage, I noticed their computers stay on for ~2 minutes before going back to a password screen for very obvious reasons.
This is obvious for me - no news.
However, I just talked to my friend working as a teacher in school here and it is kinda a big news for him. The teachers there had expectation that if you log out from Google on web you can lend your laptop and that person will not be able to read your emails.
I just can imagine how many other security holes people create by not understanding technology they use.
Client side software devs assume that a user set up a local password because there is only so much that can be done for the user, and otherwise this makes this sort of software very cumbersome to use on a continuous bases.