I couldn't help wondering why being picked up on a couple of typos was that offensive. I even wonder more why scientists do not care about typos, as they have been a group with most rigorous academic training. Perfectionism and excellence are kind of synonyme that scientists all pursue.
Incidentally, it's quite fuzzy to think in western society people don't care about mistake or trying to avoid confrontation. But, typo would be kind of low level mistake that a trained scientist would like to spend time on. That doesn't mean western scientists are so careless on misprint.
In certain professions, one typo would cost one person's job, reputation and creditability.
Not that I never have typos. But, I am thankful to anyone pointing them out to me.