Company's PR dept saying "we didn't do it" is not proof of anything.
If they're not blocking 3rd party cartridges, why even implement DRM?
Do they have so much extra money that they're developing features they're not planning to use just because they're bored?
But really, that's just Google being Google.
Even years before the "AI" hype their Assistant kept suddenly losing features that worked perfectly fine before.
Looks like not really closed-source, but not fully open as the previous printers were.
And the reasoning is the usual, other companies stealing their designs. :/
It wouldn't.
USA tried to keep the encryption all to itself in the past by classifying it as munitions, it didn't work out.
And criminals don't care if encryption is banned anyway.