Some babies need the extra comfort, from suckinb and some of them will never find their thumbs so need a dummy.
If you breast feed you may find your baby gets enough comfort sucking from that, or they may need more.
I tried with DS as even after he would delatch he still needed more comfort sucking. He hated a dummy though and at about 12 weeks found his thumb and we were finally sorted!
DD never needed as much comfort sucking, getting what she needed from a breast feed, so I never even tried a dummy. Found her thumb at about 4months.
My issue with dummies is when people (often older well-meaning but ill-informed relatives) think you have to use them as an alternative to breast feeding as babies shouldn't comfort suck you. It's called a dummy as it's a dummy boob FFS! If you breast feed and are happy with your baby comfort sucking and they are happy, you don't need a dummy. I also hate it when people just shove them at toddlers as a quick fix when they're upset, rather than working out what the issue is, or let a toddler suck one at all times of day, talk through it etc.
But if a baby needs more comfort than mum's boobs can give, or if they are FF so maybe needing some extra comfort sucking, or if they never find their thumb and need an alternative, I don't see any problem at all and certainly don't judge people who use them with their babies
Be open minded about them. You and your baby will work out if a dummy works for you.