I think the signatories of the letter - among them iFixit, EFF, various repair cafes - would be the first to decry Apple, were they actually bricking devices, and I doubt any of them would defend the practice of DRM in printers.
In fact, the letter urges the FTC to Protect “adversarial interoperability.”, which would include tools and methods to use third party ink.
As for games, most games will run without any DLC, but maybe you mean DRM? In that case, take a look at itch.io, gog.com, and also Humble Bundle.
Among other things the letter is calling on the FTC to for setting norms around providing tools and methods that enable reuse if software support ends. So it appears, they have that covered.
