I don't need to introspect. I've answered this already. His accent was just like his work: just barely good enough and no better. He'd learned English; OK, good. He could have gone a tiny bit further and figured out where the accent went.
I live in Vietnam and unlike 999/1000 other foreigners here I speak Vietnamese. A tonal language. The other Indians had done that extra work to pronounce understandably and didn't speak loud enough to make me go "ow!" all the time. Why couldn't he?
For the same reason as his lousy and illegible code: just barely good enough, and no better. He just didn't care.
And he wouldn't even answer when I asked him why he changed the status codes. I should not have had to ask. He should have let everyone know.