LO1 had a soother from about 3 days old - he was just such a sucky baby that if he'd been on the breast all the time he wanted to suck, he'd have been chucking up all over the place, there's only so much room in a baby tummy. He was EBF for 17 mos, had some bottles of EBM in the early months before I gave up pumping. My point is he took both soother and bottle and breast with no problem. I was always (even at 3 days old!) super careful just to give the dummy for sleep time, it became a strong sleep association for him, and helped him to relax. I really think soothers have their place. I wouldn't give them out automatically but for the right baby they can really help.
LO2 flat out refused anything plastic in her mouth. That's another story!!!!!!