If California starts regulating new homes without also regulating old homes it raises the value of old homes while making new homes more expensive. Who would s

If California starts regulating new homes without also regulating old homes it raises the value of old homes while making new homes more expensive. Who would support this? I think California property owners should support any and all restrictions on new homes. Who is against this? Probably a small subset of people who intend on building a home in the near future.