But it is a ridculous requirement. Like having a millsecond-hand one a pendulum clock it appears to be to precise for the timeframe involved

Why not just make it a before-date if you care for someone having been here for a time? So just proof that you have been here X years ago or longer. Totally sufficient and much easier to have at hand.

But this is of course the point. It isn't policy where the state requires a certain thing and all people who fulfill the requirement have a shot. Instead the state makes the process of demonstrating the requirement hard on purpose as a means of reducing the people who get the benefit.

And this idea isn't just unique to the described process. It is everywhere. A bit of friction in certain places is placed there on purpose and it can also be a net positive for that friction to exist. But beyond a certain level it can turn people with rights into beggars.

Immigration laws and memos (aka office procedures) are usually opaque and ambigous by design. Be it for exploitable loopholes that benefit internal production, or whatever.

Speaking of the EU, in Italy specifically for example the naturalization is really opaque and there's no clear process deadlines. While you can submit after 10 years of residence in Italy, with additional documentation from your country of origin, the process of actually getting a reply (denied or approved) may take usualy 5+ years, for some people even a decade because the people that should work on the papers forget them above a desk under a pile of dust for years.

Immagine having only third-world-like country citizenship. It's a travel nightmare.