Dr Stephen Harwood of Edinburgh University has completed an annual audit of the city's Royal Mile, noting around seven cashmere shops that have opened up over the last year.
He says the quality of souvenir shops has improved but has lead to a "certain blandness" in the street.
He said: "The sameness is not really reflecting the variety of Scottish produce.
"There's a certain blandness with what's being offered. There's a few wonderful gems but I wonder if they're being crowded."
His views were backed by Bill Cowan, planning secretary of Edinburgh Old Town Community Council.