Well, this is kind of the camp I was in. I never wanted kids, so I said and thought. I knew my wife was kind of on the fence; so I knew it was a possibility. But I was actually kind of expecting her to either A) just one day tell me she had been thinking and wanted a kid or, B) what I actually hoped at the time, her clock would stop ticking while we were busy doing us and the decision would be made due to that. We had long agreed that if we ever did do it, we'd try but if fertility was ever an issue we wouldn't pursue IVF or adoption; we'd just consider it a sign from the universe and live our lives happily childfree. But then, we (ok she) was diagnosed and overcame a huge medical issue and it had us re-evaluate our thoughts on family/life/everything in the process.

Also noteworthy is that I don't project an opinion of selfishness on others; it's what I feel of myself. I can say also, now having a lot of friends that also waited for whatever reason, it's not uncommon in this cohort. It's also very common that people wait then run into fertility issues and the feeling hits harder for them. We've known a ton of people that struggle hard with that, more-so if having kids was already on your must-do list and you just delayed it too long.

So to answer your question more directly, I don't think the person you described is selfish. They may however realize they were if they ever decided to actually have kids and perhaps have some regret do to that.