Maybe it's different in the USA, but I've travelled a lot and don't think I ever remember a long haul flight without multiple babies and young children. It's just a fact of travelling.
I recently did a 16hr flight solo and the other 3 seats in my row of 4 were parents and a toddler.
That's just part of flying and you should plan for it (noise cancelling headphones, sleeping tablets, ear plugs).
kids crying/screaming on public transport/etc rarely bothers me. impatient parents hissing at them to shut up and sit down does, however... i get it, they're tired, being a parent is hard, but still.
a kid cries on the tram? i keep reading, barely even notice
a parent goes off on their kid? rips me right out of the book and makes me take notice
We've flown a lot in the US with our now 2 year old to visit family, and have never had anyone say anything to us on a flight in a negative way. We've had a lot of people tell us how great our son did even if he got a little fussy here and there. We've flown first class with him several times and no issues.
I'd say we're lucky that he is a little rockstar and handles it very well, but it is definitely stressful for us but just part of what we have to do sometimes to see family. I feel terrible for people that have to do longer haul flights with smaller kids though, 2-3 hours is manageable but if we had family overseas we would probably fork over the cash to fly people to us rather than put him on a plane for that long. For our sake more than his lol.