Local case studies from Europe en elsewhere show that:

Clients coming by bike spend more than those coming by car, be it during a certain time period or related to the parking space that has to be provided for them. Car drivers might spend more per visit, but they visit shops less often. Cyclists do their shopping locally, and are more loyal customers.

Retailers often under-estimate the share of clients that go shopping by bike, and over-estimate the share of car
users among their customers.

If a street is transformed in a way that gives more space to cyclists and pedestrians and less to cars, the absence of clients that came by car before is more than compensated for by the clients that come by foot or by bike afterward.