If you define flirting as attempting to initiate a new relationship with a woman you don't know or barely know, that's how relationships between man and women start. There is almost no way a man can openly start a conversation and not be criticized by the current culture. Women live in this protective bubble with walls build up by this constant undercurrent of misandry.
Men are very reluctant to approach a woman in a group setting for fear of being humiliated by a woman enforcing her rights as as woman. It doesn't pay to make the first move. Woman are ignored because they want it that way. This is so ironic since woman invest much more time and money into their appearance only to be ignored.