Well, it's real now!
https://www.nytimes.com/2019/01/22/technology/australia-cellphone-encryption-security.html
Apple should have done that long before. Microsoft did that.
My bitlocker enabled computer reopens a video on Chrome before I log in. That's the best evidence that bitlocker doesn't really lock your data (well, it does, but the key is not properly stored).
Unlike Apple's attitude to FBI's investigation (that California terrorism case), Microsoft bends to all governments across the world.
That's why it's far less boycotted by many countries.
A better name for it would be Data Decryption Law.
They can just save the effort and learn what China did on the same case.
We just don't allow end-to-end encryption. You can do that privately, but no public commercial communication platforms (apps, websites) are allowed to offer such service.
Saves the government's time and taxpayers' money.
How can they enforce it? I can always install an app that offers encryption.
If the government wants to ban something, it will just audit the heck out of whichever company that stands in their way.
There're no perfect companies. Everyone has some minor problems, being tax, OSHA, fire safety, data privacy, etc.
If the government wants to fuck you, it will find a legitimate way to do so.
Want to write your own app? Fine, but as soon as you get into business, the gov't will come back to fuck you.
Want to keep under the radar? Then you will never be able to recover the R&D cost.
So without economic incentive, no one will do so.
BTW, check out the outcome of the author of TrueCrypt. He was a gifted programmer, forcibly and very likely wrongfully given the name as an "international crime lord" and "ISIS supporter".
That's what comes to you if you defy the government. Be wise.