Before kids, you take a look around a diner or a store or a playground and you see little ones happily eating some chips or browsing the foodstuffs or playing on a slide.
You think that this is what kids are like. They sit there, they walk a little, they giggle on the playground, they look cute as all get out, etc.
Then you have kids and you know.
You know.
Those kids sitting there in the booth sipping on their milk quietly while mom and dad happily eat their lunch? Those are the top 5% most calm kids out there. The other 95% of kids are with their adults screaming and throwing fits and covered in who knows what.
Life lied to you. It did it directly to your face, unashamed. The bias is real.
That's not the impression I hear from my many intentionally childless friends. They take the negative behavior - the screaming, tantrums, chaos - as the norm.
It sounds like you always wanted kids. I don't say this to criticize - it's great that those who want to start families do so - but I don't think your experience is universal.
Oh then it's even worse! As again, only the more well behaved kids are going out in public.