I’m thankful that my kids fly well, and always have. We flew with them at ~15 months with no issues.
I’ve always heard the complaints about screaming infants and whatnot…but I’ve never seen it. Granted, I don’t fly too often (and less so more recently), but I’ve never had the “classic” kid crying through the entire flight. It just doesn’t happen as often as people think. I’m sure when it does happen that it’s pretty f’n annoying, though.