Of course 'Carry On Emmannuelle' is a film some fans would like to forget. It was the first of the series to go further than any of it's predecessors. The main theme and subject was, well, sex. It seemed to lose the magic of the series and gone were the double entendres and most of the core 'Carry On' team. By this point stars such as Barbara Windsor, Bernard Bresslaw, Charles Hawtrey and Hattie Jacques had departed the series and Sid James had died in 1976.
The series now had films such 'The Confessions' films to compete with and social attitudes and interests had started to change. The scene Malcolm was in is case in point. Despite a few subtle nods to homosexuality in previous films, such as 'Carry On Abroad', this scene has a overtly camp gay guy seducing a Sentry. Stereotypes were now at full throttle.
I don't actually mind the film, it is what it is and is after all it is the last true 'Carry On' with the original team. I think that it was just a poor choice of subject with all the other material and scripts Rogers and Thomas had at their disposal (such as 'Carry On Again Nurse') - see section 'The Lost Carry On's'.