1) It was good of you to say something - hopefully the OM will not react the same way next time.

2) The problem was initiated by the woman not taking due care with her bag and she hopefully has also learned to take more care next time. It also probably wasn't a good idea for her to say "I didn't do it deliberately" - that can potentially be interpreted as it was sort of OK because it wasn't deliberate, or a degree of belligerence. It probably annoyed the OM quite a bit. An additional "I'm terribly sorry, I'll be much more careful in the future" would have gone down better.

If both parties modify their behaviour in the future, then it was sort of a productive outcome. Lessons learnt are always productive for the future even if it was unpleasant at the time.

It can actually hurt a lot when an object hits the glasses though, even if the impact is minor so it's possible that the OM's over-reaction was triggered by unpleasant sensation that came as a bit of a shock, and the discomfort can linger for a while. Is it possible that the he was in discomfort rather than sulking?

I anticipate being hit in the face when seated in the aisle seat and lean towards the window to avoid it, especially in winter when the overcoat-edge/button-in-the eye is one of the rather common occurrences. If I did that to someone and had an upsetting encounter as a result of it, I would not expect an apology from someone whom I annoyed, even if he/she had over-reacted - it's my fault to have initiated the situation.

I have actually received injuries (not just once either) from being hit in the face by people's belongings during boarding process so I am a lot more cautious nowadays.

Curiously not many have even ever noticed having hit me (or anyone else for that matter) in the face with their belongings or apologised. About 1 out of 10 results in any form of apology. Probably because I don't really react much but really, I think a bit more awareness of where their belongings are would not go astray.