there is no anonymity on the internet. the sum of your devices characteristics are close to unique anyway (i could be wrong but i think this is accurate). which kind of supports the hypothesis that this is about shifting responsibility for age verification due to laws coming from other countries recently. i have no idea how this will work on linux, it probably wont.
Firstly, you keep using that word; I do not think it means what you think it means.
On the Internet, especially forums such as HN, you are "pseudonymous". That is, you made up a name for yourself, and that's how you're known to others. At the very least, we are all identified by IP addresses, which are again, fairly stable and unique pseudonyms. There are nearly zero truly anonymous corners of the Internet, because anonymous communications are chaotic and anarchic.
Secondly, it was the NSF who mandated that everyone accessing the Internet must have an associated and authenticated account with an identity that is known to their provider. These rules went into effect in the early 1990s. Perhaps they have been discarded or observed only in the breach, but truly, nobody is a stranger on the Internet. Even if nobody knows you're not a dog, your ISP or your coffeehouse still know who you are, when you connected, what device and so forth.
So, please let us stop pretending there is "anonymity" here, or that there ever has been. Whatever you've done in the past, it will eventually be unmasked. Yes, people on Discord and Wikipedia alike are freaking out over this prospect, but it was always going to happen. We've been laying down a very permanent record for over 50 years. Eventually it will all be correlated with real identities, Facebook or not.
The NSF "rules" stopped applying when the NSFnet was shutdown in 1995. Actually, earlier, since commercial providers (upstream ISPs like UUnet, Sprint, MCI, PSI) were not dependent on the NSFnet and did not have to abide by the AUP.