It has been described more than once as the best example of film-making ever (or even as simply the best film ever). My old boss used to be a big fan. He didn’t think that any scene could have been done better than it was (I wondered if an abduction by space aliens, in the background probably, might have livened up the scene on the boating lake a bit).
There might be casual sexism in the movie itself but it’s still quite rare in that Celia Johnson (female lead) was paid more than 20 times as much as Trevor Howard (male lead).
Come to think, I’ve got another friend who reckons that Trevor Howard’s character is not the gentleman he appears to be. He’s actually a predatory sex-pest who’ll be hanging about on the same station the following week trying to chat up another bored housewife.