It would appear that us manual workers are been compared to white collar workers by some.
IMO it is possible to be clean, smart and comfortable in shorts and still be complimentary to your professionalism.
OK, it is rare to see a sales rep, vicar, accountant, solictor, judge, bank manager et al in shorts. They are all involved in sitting and walking in their professional lives.
But carpet cleaners, postmen (forget the sexism bit

) builders, carpenters, plumbers, milkmen et al are all involved in lifting/moving weights and manual work. Can you now see the differences in the nature of the different trades/professions being compared by others?
To make matters worse for CCers, we are working with HOT water, and when working upstairs, the heat from within the building as well as our equipment will find it's way up there. Has anyone here tried brushing in protector on a first floor carpet on a really hot day?
As for the comparison with warmer countries, air conditioning is more commonplace, especially in commercial premises. And as a good rule of thumb, the UK tends to be very humid on really hot days. Just compare it to a sauna. You pour water on the coals, the temperature stays the same but it feels hotter and stickier. Our work increases the house's humidity considerably.
At the end of the day, it's a personal choice, shorts or trousers, as long as you are considerate to both your clients needs and your own image.
And finally, you could have wonderful legs like mine, or you could have legs like Derek Bolton

Safe and happy cleaning

Ken