There are many things wrong with Newsom's policies, but characterizing the end of single-family zoning as "crushing suburban American dream by eliminating single family homes" is rubbish. The American suburban dream in California has already been crushed by confiscatory tax policies, the lack of enough areas zoned for multi-family dwellings to absorb some housing demand pushing house prices even higher than they otherwise would be, and the generally anti-business (esp. anti-small business) policies of the California government.
If anything, allowing more multi-family housing construction will moderate prices on existing and new single-family dwellings, which would benefit the "American suburban dream".