No EASY is not just for FF babies. My two never had a drop of formula and I fed them both until 2yo, mostly on an EASY format.
We never had any issues of not wanting to feed when waking for the day or from a nap. We did deal with distraction at the 4mo point but that was easily remedied by feeding alone in the still dark room upon waking from a nap.
We never had growth issues or supply issues. Mine both scaled the growth charts while EBF from 0-6mo.
I think it is widely known and accepted that breastmilk contains a range of hormones, including oxytocin, prolactin, melatonin and cholecystokinin, which all help relax mother and baby. That is often why babies get that drunk look after BFing
Breast milk also changes throughout the day so milk at night contains melatonin which it doesn't really have during the day. Possibly a stimulus for sleep-wake cycles.
If EASY isn't working for you then trying something else is only natural. Tracy always said something is only a problem if it's a problem, yk?
I'm glad I taught my kids the ability to self settle, not least because it means someone other than me can put them down to sleep and I didn't have to feed them every time they woke at night when they weren't hungry.
Evolution is a wonderful thing but the fact is our lives have changed unrecognisably since we evolved. Personally I choose not to share a bed with my kids and have them feeding on demand day and night. I don't sleep when they sleep (because don't forget those same hormones make mum sleepy at each breastfeed as well) and I want them to be able to put themselves to sleep without being dependent on the breast. Maybe that is against science but it isn't harmful I shouldn't think and it is more practical for my modern life and it works for us which I think is the main thing