I feel like too many people take being corrected like this as a sign that I’m trying to be condescending when, to me, it’s a simple courtesy I hope other people extend to me as well when I mess up.
To be fair, sometimes the timing of correcting someone can play a role. Waiting to correct a spelling error until after the main point has been discussed is usually best, otherwise it can be perceived as condescending.
Whether that was the case in OP’s message or not I cannot tell from the bit we have.
The human brain really fuckin hates being wrong. To the point it will create false memories to prove it’s right. This is a recorded psychological phenomenon.