Dummies are great, definitely no rod for your own back.
I would call it independent settling, as opposed to self settling.
True self settling is not possible until the child is of pre-school age because research has shown a child does not have the emotional brain capacity to sleep as an adult would (tired, lie down, close eyes, sleep - both when going to sleep and also during the night for slight wake ups).
Until then babies need something to offer then comfort and security to help then sleep. Many parents become this comfort (BF to sleep, rocking, cuddling, carrying, holding, patting, or indeed just their presence). The joy of a dummy is that baby can settle without the involvement of an adult - they settle independently.
Effective use of comforter toys also allows for independent settling. Or thumb/finger sucking. Or self-stroking, self-tickling or hair twiddling. Most of these come with an older baby though.
A sight aside would be that within the first 4 months of babies life, many babies can easily fall asleep in this newborn phase because basically they are just programmed to feed and sleep at this age. But as baby gets older, sleep is less easy to come by and dummies come into their own.
At some point you will need to get rid of the dummies. But handled well at a time when the child is emotionally ready for this, I have never had any difficulty getting my three children to get rid of their dummies.