The user has been "programmer_dude" for 6 years just on HN, there's no chance that they didn't learn about the dot. I'm confused as to how they can be confused

The user has been "programmer_dude" for 6 years just on HN, there's no chance that they didn't learn about the dot. I'm confused as to how they can be confused. Even in my comma-as-separator country, our calculators have a dot. The only thing that could be confusing is encountering numbers with 3 decimals: 123,456 vs 123.456