Easyjet to Malta last month insisted upon masks both outbound and inbound. The Maltese had strict mask wearing for indoor places.
Three weeks later, Tui to South Teneriffe and return, the airline didn't give a stuff. This despite the Canary Islands, at least the one we were on, also having strict mask wearing when indoors. Indeed on a ferry to the island we were staying on, one of the stewards was walking round ensuring people wore masks.
Sure, there was an announcement by the Tui staff on the plane about recommending mask wearing, but none of the cabin staff nor for that matter flight deck staff, wearing them didn't set a good example. Which came as a shock to me, given my earlier experience with Easyjet. And of course, as soon as the announcement was made that it was not compulsory on the flights, masks came off. As a result of which, based upon the aircraft I could see, there were probably at most a dozen people, including my wife and I, who wore them throughout the flights.
Edit: I await with interest what Easyjet say next month when I fly to Egypt. Although then I shall be taking one of the FFP2 masks as both my wife and I have come down with Covid since the Tui flight.