If you're making a sober economic assessment of the cost of children, it's not a different issue, it's a typically-very-large cost that must be considered.
You can argue the costs down from 'house note' to 'very-nice-car note' or even 'cross-your-fingers-and-maybe-it's-almost-nothing' -- one can certainly (effectively) self-insure with the same sorts of outome-roulette as not providing for your child's education.
But you can't just hand-wave away the issue.
I'm not saying that things are exactly the same as when you don't have kids, but it's not nearly as bad as some make it seem. Being socially well connected with family & friends help too. When we need babysitting, grandparents are more than happy to help. We tend to attend parties where other parents will be and the babysitting often gets older kids in the party. I've never appreciated having close community connections as much as I do now before having children.
Blanket expensive is not the status quo. But I must admit, if you're a single parent with little to no family and community support, it can certainly be expensive.
Most people I hear complain about how afraid they are of the expense of raising a child are more in my position where it wouldn't affect them that much. It's more reflective of the fear and negative bias then what the reality is. Having lots of money on kids is definitely nice though and will make lots of things in life easier for them, but it's not a must.