Okay... I don't even like Ubuntu, I'm still pissed at snaps, but I'm going to call it bullshit. OP is being at the very least disingenuous, if not worse (witch hunting).

Ubuntu Pro is a subscription system with the following features:

• Extended security maintenance - 10 years of backported features, because enterprise hates dist-upgrade. By then human users upgraded their systems at least once, probably way more.
• Live-patching kernel updates - because enterprise hates restart downtime. If it's your personal machine you simply reboot after installing a new kernel, no biggie.
• "Compliance and hardening" - basically a way to ensure that a machine follows a bunch of security protocols irrelevant for human users, and exchanging usability for less surface area in a way that human users wouldn't want.

Are you noticing the pattern here? It's junk that enterprise cares about, but you don't. Canonical is milking corporations.

To make the comparison with airbag vests even worse, Pro is free for personal use, up to 5 machines. So it's more like Canonical is saying "since we know that stupid bizniz bureaucracy prevents them from regularly replacing airbag vests, we're willing to repair them for a price. For free if you're a random nobody, by the way."

And no, it does not contradict the Ubuntu principle, as your title implies.

And since I can't be arsed to rebuke this shite being cross-posted to !latestagecapitalism@lemmygrad.ml, I'll do it here. (I apologise to the others for posting politics here.)

The airbag vest part alone would be a good example of late capitalism; the business is clearly seeking to add surplus value to the goods. And since that surplus value cannot come from paying less for the labour of the workers, it comes from the buyers/"subscribers" - transforming the goods into a service, and commodifying personal security.

Ubuntu Pro is not this, as I've shown above. But even if it worked somehow like you're implying that it does, through both threads (i.e. you don't have ubuntu pro = you don't get security updates), it would still not be an example of late stage capitalism: security updates are a service by nature, requiring additional labour to be produced, specially when you're backporting a patch to ancient software.