We had one when I was a kid that wasn't, but you're right majority were sold in a cabinet of some kind. I remember my mom's screen going green at end of it life. But it was like from the late 60's or early 70's.

Can I backup my computer software?

Yes, under certain conditions as provided by section 117 of the Copyright Act. Although the precise term used under section 117 is “archival” copy, not “backup” copy, these terms today are used interchangeably. This privilege extends only to computer programs and not to other types of works. Under section 117, you or someone you authorize may make a copy of an original computer program if the new copy is being made for archival (i.e., backup) purposes only; you are the legal owner of the copy; and any copy made for archival purposes is either destroyed, or transferred with the original copy, once the original copy is sold, given away, or otherwise transferred.

Frequently Asked Questions About the Section 1201 Rulemaking

What classes of works did the Acting Register recommend and the Librarian adopt in the 2018 rulemaking? Video games for which outside server support has been discontinued, to allow individual play by gamers and preservation of games by libraries, archives, and museums (as well as necessary jailbreaking of console computer code for preservation uses only), and preservation of discontinued video games that never required server support

You actually own a specific copy. DRM or not, does not change it.