I can’t say that I necessarily agree. I don’t think there is anything wrong with flirting with a woman in public unless of course it is obvious she is involved with something serious. From my experience, women will let you know if they are not interested and then you drop it but merely the suggestion that a woman would not be interested just because she is listening to headphones or whatever is simply not true.
I have been approached and have approached women in a public space respectfully without negative repercussions. In some cases, they were glad that I initiated with them and some cases they were not. In either case, I respected their wishes and thereby respected them.
You can respect women and still approach women in public. The two are not mutually exclusive.