Yep, another voice adding to the throng here OP (and pleasantly surprised to read so many similar responses on MN as I have never in RL encountered anyone who'll admit to feeling the way I did/do!)
Never remotely maternal, I never really found kids cute or endearing, just noisy and hard work. I liked/loved my nephew and had an amazing bond with him but he was the exception that proved the rule! Never cooed over a baby, actually if anything I found them quite unappealing (that sounds awful but just trying to be honest).
I now have a DD after YEARS of putting it off because I just never really was sure I wanted it enough. She has changed my life for (only) positive, and I worship the ground she walks on. She isn't easy, she is a lot of work, but my God the difference when it is YOUR child and not someone else's, is amazing. I would do anything for her.
By nature I am quite selfish and yet somehow I have found selflessness I never knew I was capable of. I am not cuddly or able to 'do' physical affection with other people but I can barely put my DD down, I would cuddle her all day if she would let me (fortunately at 3 she is still a complete cuddle monster)
I am getting to know and really like some of her little friends but i by no means particularly like or bond with all the small children I now know just because I now have a child. So that aspect of me hasn't changed at all!
A friend handed me her baby a few weeks ago and I just have no idea what to do with one still - a baby that isn't mine feels all wrong in my arms, just as it always did.
I think it can be hard to understand that maternal feeling if you just aren't that way, in the same way I imagine it might be hard for a person who just loves all kids and has always yearned for loads of their own to understand how it feels not to be that bothered about children per se.
But yeah. Just another voice here saying that I don't/never did have a particular liking for children, but my own DD is another kettle of fish entirely. Best thing I've ever done, she is my entire world.