I don't have a so-called BBC accent and have always had a regional accent which I've had to "modify" over the years in order for certain people to understand properly what I'm saying.
Nevertheless, I never speak in my "true style" unless with those from my "neck of the woods", for the simple reason that I only have to reiterate what I've just said.
There are many regional accents throughout the UK and the Scots accent is certainly not the only one which some people have difficulty understanding.
But this was no "racist" incident. Had the remarks been made to Ms Harman and colleagues by anyone with strong Geordie, Brummie, Scouse, Welsh, Irish or cockney accents, would she/they have struggled to comprehend what was being said? You bet they would !!!
A storm in a teacup, no more than that - at best !