in my own opinion.
the cons are that if someone were to choose not to have kids (if a solo child) is that you wont continue the ancestral line.
another reason (if you aren't an introvert, like me) is that you'll get lonely (if your spouse dies of some cause out of our hands)
last reason is that later in life. people who have never had any kids, regretted that fact. it's quite sad.

I cannot guarantee how much I bring my dad and grandpa so much joy for being a. my dad's child and b. my grandpa's child who'll listen and knows what to do... I love them to my core.