Nothing in the Municipal Density and Missing Middle Housing Act shall be construed to prohibit any city from:

(1) Regulating the siting and design of middle housing provided for under section 19-5505, except that such regulation shall not prohibit or have the effect of physically precluding the development of middle housing in any residential area; or

(2) Allowing single-family dwellings in areas zoned to allow for single-family dwellings.