I was in Chile in 2017 for a census operation and the whole country shut down to conduct the census. It was a pretty big deal while I was there (and also a bit inconvenient because everything was closed). There was a lot of talk about how there had been a previous attempt at conducting the census which had ended up being a huge failure and how getting the 2017 census done right was a point of national pride.

I also worked as a canvasser in 2019 and 2020 for the US census and, while we were about as thorough as you could reasonably get, the whole operation made me somewhat skeptical of official statistics in general. 2020 in particular was a bit of a disaster due to the pandemic and when the statistics were published, a bunch of mainstream news outlets published stories about certain areas experiencing "population decline" and all I could think was that those were actually the areas where the census didn't manage to count everyone.

I used to do canvassing and yeah, I never believe official stats anymore.

Especially anything that's self reported or whatnot. People lie. People misunderstand questions. No process is perfect.

Over here we just have every person registered in a central database from birth and it's mandated by law to keep the registry updated with your current address. The last census was in 2001 and then there was also done a big job registering every residences in multi residence houses. The assumption is that we will never have to do a form based census ever again and just use central registries instead.