TL;DR;

• The field isn't the issue, the intent behind it (and the intentions behind the law that started it) are what (most) people are complaining about.
• Pretending that people are complaining about the field itself in isolation as a means to not address the actual concern being raised is weaksauce.

Let’s say the answer is “Guaranteed”, in 5 years age verification on OS level will be mandated by law in US. Will it become mandatory on all Linux installations? Of course not.

If the law mandates OS level age verification, then, yes, it will become mandatory on all linux installations, in the situations where the law applies. there is no "of course not" about it.

Will everybody adhere to this? almost certainly not, will it be illegal to not adhere to this yes it will.

Anyone willing will just download Linux distro for any other country and use it.

Agreed, still illegal though.

Let’s say age verification will become mandatory in the whole fucking world and all official Linux distros will adopt it. Anyone willing will download “illegal” Linux distro and use it.

Also agreed.

The source code is there, making a version of Linux without age verification is and always will be easy.

Easy is a leap, i'll agree to possible. Still illegal in the proposed scenario.

The changes done by systemd are meaningless because they do no bring us any closer to real enforcement.

I'm not disputing that the actual change itself is of much use in a verification sense, which i've said repeatedly.

Technically , by definition, the addition of code that facilitates checks, no matter how small, is bringing us closer, but i know what you mean and I’ve already stated that i agree.

The issue being raised is not the PR itself, but the intention behind it (and the intentions behind the law that started it) , as has been stated multiple times.

Police knocking on people’s doors and checking their computers will bring real enforcement and what systemd does or doesn’t do has nothing to do with it.

Also not true, that example doesn't really hold up , but to answer it directly :

• If the field does exist and is incorrect (or empty), that's something they can try to admit as evidence.
• If the implementation of the field exists and this particular build/compilation doesn't include it,that is also a kind of proof.
• If the field never existed in the first place it's absence can't be used to prove anything.

To be clear I’m not saying this to claim a position of "field is bad on it's own", i'm saying your example doesn't hold up.

Getting mad at systemd for adding this field only shows people don’t understand what the real danger is.

As i have said multiple times, most people aren't arguing against the field itself.

You continuing to pretend they are mad at systemd for the field itself is telling.

You’re conflating political issues with completely irrelevant technical changes.

No, I’ve been clear that they are separate and that most aren't complaining about the technical change in isolation.

I'll quote myself:

This field is not age verification on it’s own.

Nobody is pushing this single field change in isolation is a full age verification system, to pretend they are is disingenuous and reeks of bad faith.

If you want to continue to pretend conflation so you don't have to actually address the concern being presented that says a lot.

This is very simple. I really don’t know how people are confused by it. It’s like you are trying to distract us from the real problems on purpose.

So, incorrect usage of a fallacy, moving goalposts, feigned ignorance , and now projection.

Is there some sort of bingo card you're working from ?

Anyway, I’ll assume bad faith at this point, as it's unlikely you hit that many checkboxes accidentally.

On the offchance I’ll get a genuine answer, what is it that you think is the "real problem" here ?