Comment by wesselbindt

https://thestory.is/en/journal/chaos-report/

^ This report from 2020 analyzed about 50,000 IT projects in a wide range of market segments, and they found that 50% exceeded their deadline. This seems to suggest that your conclusion holds more generally than just your specific context.

On a personal level, I hardly ever see a developer's estimate turn out to be right, on whatever scale. I'm wondering what the pro estimate folks in this thread work on that they're able to estimate accurately.