Bullshit. It would not outlaw single family homes. It would just allow multi family homes as well as single family homes.
Restrictive zoning is one of the things that drives real estate prices up, creates NIMBY factions and prevents the market from organically correcting itself.
Single family zoning prevents retired people from converting garages or basements into an apartment for extra income, prevents the addition of MIL units and many other types of remodeling that people often want to undertake when life throws curveballs.
Restrictive zoning is a dumb idea made worse by dumb bureaucrats trying to predict and control future development.