God there are some odd viewpoints expressed on here.
Co sleeping is entirely normal at this age and so if nursing even in the night.
It also isnt co fusing for little ones, he knows mum can nurse him snd dad can do what works best for him, so a cuddle,,pat on yhe back etc. I remember when one of my boys woke in yhe night he ofer curled up on his front and liked someone to pat his middle back.
There are lots of ways dad can soothe snd support his sleep, he just needs to work out his own method. And little one will know he does X with dad and nurses/co sleeps with mum.
Bfeeding wont harm his teeth its not link mulk from a bottle in night that pools in mouth around the teeth. And tyere is lots of advice and information on rgis but bfeeding and collecting through toddler years is very normal biologically.
My children are 26, 23, 21, 17, 15 and 9. They all co slept and fed, generally by 3-4 yrs they stopped co sleeping. They just grew out of it. 2 nursed for much longer but again they grew out of that as well. All well adjusted and sleep fine as adults. They can even remember bfeeding and my 9 year old will occasionally reminisce about it. He doesnt want or need to nurse but he talks fondly about how safe it made him feel.
Secure attachments are fundamental a childs development so keep on doing what works, he will stop when he is ready.
Unless dad is prepared to cone round and do 100% of night wake ups snd resettle him he doesnt get to tell you what to do on your nights.