[ericmay]

> If it's just paperwork then surely nothing bad happens not following it

Well not filling out the paperwork means you'd be in the country without authorization which you know just subjects you to being deported or fined or to face other penalties depending on the laws and regulations of that country. So to your point, nothing really "bad" per-se happens by not following it. You just might be deported or fined and then you have to just accept that reality.

> Note that I'm not defending unlawful immigrants; but once you spend a large amount of life in a country and you did nothing bad I don't see any issue with said country allowing you to stay.

Sure, but conversely if that country decides you're not allowed to stay there's nothing wrong with that. Just being in a country for a long time doesn't retroactively grant you citizenship or anything. Though some countries may from time to time decide that it does, which I find unfortunate especially for those who are pursuing the proper methods. We shouldn't encourage breaking of rules or laws in our societies as a default.

> Of course having a safe legal path to residency

Well in the US at least we do have a safe and legal path to residency. Most other countries around the world are far, far more strict on these requirements.