My bet is 80% of complaints aren’t directed to the airlines.....
Your probably about right, and the same goes for any business which is why a business must address each compliant with the seriousness it deserves.
So far as the airlines are concerned, front line staff are sympathetic and appear at times appear to share in the grief somewhat, yet they are often powerless to change anything in system where front line realities are a world apart from head office perceptions.
Imagine a world where the basics where sorted before embarking on the pomp and grandeur of game changing product offerings that are anything but.