Not OP, but I was sterilized in my mid 20s. Not only am I not interested in having kids, but I would not be a good parent. I have still dated people with kids who made it clear there would never be an expectation that I become a parent or interact with their kids, which does address those issues, but there are others. Understandably their kids take priority over basically everything except for maybe the factors that effect their ability to provide for their kids (or at least I think they should). That often means they don’t have nearly as much time to hang out and build a connection, nor are they able to be as free to do other things due to constraints on their time, finances, or both like going on fun trips. Another factor I have run into that is that usually the reason someone is single and has kids due to entirely positive reasons, and there is often at least some amount of trauma in their past that is often not entirely behind them.
To be clear the above is in no way an absolute and are merely my anecdotal experience and correlations in the given area I live. It is also always worth keeping in mind that I am in no way perfect myself and that it’s possible there is something about me that results in the above being my experience.