Maybe you expected him/her to be excited about the exit but that not being the case does not mean you should have repled with 'rude sarcasm'.
You could have used the opportunity you used to respond to learn about competitors in the space however you chose this route.
I have noticed several senior (by karma) HN members that take an unecessary offensive approach towards comments that do not "tow the line".
Maybe you expected him/her to be excited about the exit but that not being the case does not mean you should have repled with 'rude sarcasm'.
You could have used the opportunity you used to respond to learn about competitors in the space however you chose this route.
I have noticed several senior (by karma) HN members that take an unecessary offensive approach towards comments that do not "tow the line".