There are a great many women out there who would like to be breastfeeding, but can't, for various reasons. And the amount of guilt and shame experienced by many in this group, because of the glib culture surrounding breastfeeding, is doing severe and lasting damage to many parents' mental health.
While not optimal, formula is a healthy and viable alternative. That's really all that needs to be said about this.
Oh, and everyone feeling entitled to, nay, obliged to tell you how to do your job.