In May, in Toronto, KLM did not like my (just) legal carry on camera bag; too big and too heavy. I had to repack in front of the ticket counter and my wife had to take some equipment into her carry on, some had to go in luggage.
Coming back from Amsterdam, no trouble at all. Meanwhile, many ladies were carring on purses the size of steamer trunks as well as carry ons. They didn't think my 4x5 and medium format was personal.