The elements of Istiklal’s decline were evident well before the recent downturn. For years, the city’s intelligentsia bemoaned the changes taking place not just on the street, but in the entire neighborhood, called Beyoglu. Once a cosmopolitan place of old cinemas, bookshops, outdoor cafes and dive bars, it had evolved under the Islamist government of President Recep Tayyip Erdogan into a tacky urban space dominated by chain stores and faux-Ottoman shopping malls.

“All the characteristic landmarks that made Beyoglu special disappeared one by one,” said Mucella Yapici, a member of Istanbul’s Chamber of Architects. That group has opposed many of the government’s urban development projects, including the one for Gezi Park, at one end of Istiklal, that set off antigovernment protests in 2013. “And the neighborhood turned into a place that entirely lost its soul. Old taverns, bookstores, theaters, and especially movie theaters, shut down.”

The government, Ms. Yapici noted, has removed the protected status of some historical buildings to make way for new ones. It also changed the law to allow longtime tenants, whose rents had been below market rates, to be evicted. These tides claimed one of the most famous places on the street, an old corset shop.

What replaced the old hangouts were chain stores, fast-food restaurants, fancy cafes and shopping malls, all of which are now feeling the effects of a declining economy brought on by a fall in tourism.