Restores the Coastal Commission’s authority over housing that was eliminated in 1981, including authority to require local coastal plans to include housing programs; Requires, with exceptions, that new development preserve and enhance the supply of high density residential, multifamily residential, and mixed-use in areas with adequate public transit; Requires that affodable housing opportunities be protected, encouraged, and, where feasible, provided; Requires local coastal plans to established streamlined approval procedures for supportive housing and ADUs.