They've had black shorts with the red shirt before iirc.
Our identity is more with the sky blue shirt. I suspect most people aren't too bothered about the colour of the shorts as we've worn blue shorts in the past.
You suspect wrong going off the vast majority of posts on bluemoon on the subject over the last 4 years, mate.
The Shite wear black shorts sometimes when there's a colour clash. But their home colours for the last 40 years has been:
Red shirts, white shorts, black socks.
Arsenal red shirts white sleeves, white shorts, red or white socks for the last 40 years bar their anniversary season.
Liverpool red red red for the last 40 years.
Chelsea blue shirt blue shorts white or blue socks for the last 40 years.
City sky blue shirts, white shorts, blue socks for 90 years, and then Swales let Umbro mess about for a few seasons, and nowadays, who knows?! Sky blue shirts and then whatever the designer feels like when he wakes up that day!
No other top club in the country gets their identity messed about with like us. Maybe it's not important to the designers at Nike, but it's important to a lot of our fans.