We don't have to look far into the past as to what happens when DRM enters the picture.
Take the humble Commodore 64. The most common home micro of the 80s.
Lots of users. Lots of software. Lots of piracy.
What happened in the end is that lots of companies making software made lots of money, despite the piracy, until the computer faded into obscurity with a dwindling userbase that had moved on to more powerful computers.
All DRM "disk copy protection" was eventually broken, and just about all game software ever released for the computer is downloadable online (you know where to look). The end result is that we have a nice digital archive, complete with emulators, left for historians or anyone who wants to relive what it was like to use the machine in the hight of it's heyday (or simply to see what all the fuss was about playing "Impossible Mission" or something)
If it wasn't for the pirates and crackers willing to ignore the ridiculous copyright law time extensions, copy programs to different countries where they were not available for sale (over the pre-internet BBSes) chances are we might not have a digital archive, or at least be missing important bits. By the time the copyrights expire, the magnetic media, if anyone still had any left, would be corrupted by bit rot, and the equipment needed to read it may not be in a working state or readily available.
So the Commodore 64 avoids a digital dark age, but I have my doubts about some heavily DRMed content going forward.
In many cases, if something is heavily DRMed and people do not make the effort to break it, it will likely be lost to the digital dustbin of time.