It seems to me that all of the reasons they provides are all reasons to get married. Especially raising a child, given the privileges that are afforded to married parents in a lot of places (especially in the case of adoption, or IVF using a stranger’s genetic material). Something doesn’t have to require marriage for the benefits of it to outweigh the cons for a specific situation.
The question seems to me to be kind of confusing. What alternative are you comparing it to? Some sort of local structure like domestic partnership?
I’ve encountered IT departments with an unencrypted passwords.xlsx file that they store on the network. Not always super small companies too.