This topic is really fascinating me as I wanted to formula feed DD3 for a multitude of reasons, felt guilty about it and initially breastfed her! Long story short, baby was starving, topped up with formula while still in hospital - and gradually moved to EFF. She’s 5 week and perfect! Tracking us around the room, able to lift her head up for several minutes, babbling a bit, sleeping, no reflux, gaining weight etc, etc.
I EBF DD2 for 27 months. It was bloody hard, no sleep until just after her second birthday, and she only weaned when my milk dried up when 12 weeks pregnant. She has CMPA and a soy allergy. She’s equally bright and perfect, but I believe the antibiotics I was taking when breastfeeding her in the early weeks sensitised her to those proteins (altering gut bacteria etc), she was also ‘dairy’d’ countless times through my milk when I unknowingly consumed it via a takeaway or something. Anyway, it was damn hard, and she managed to still catch colds etc, etc. Did the benefits outweigh the toil? No.
DD1 was EBF until 3 months and combi-fed until 6. She’s a teen now and recoils in horror at the thought of ever been breastfed.
No difference long-term between breastfed or formula. And I would argue many of the differences come down to other variables at play - education level of the parents, support systems, and so on.
Do what you’re comfortable with, all your baby needs is your love and care (+ nourishment in whatever form).