I think that's common in most places. What's different in the US is that the IRS forces you to proactively provide a lot more information about it, though. I have a rental property and need to enter the same information about the same income and expenses on three different forms, breaking it down in different ways. It's tedious and error-prone, and I guess the philosophy is that it's easier to spot fraud if the numbers on all the different forms don't add up to a coherent story.

Other countries presumably rely on other fraud signals. They might have more visibility into your day-to-day financial transactions, or there might be more of a culture of leaving an anonymous tip if you suspect your neighbor isn't paying a fair share.