Of course that does not increase affordability. We're speaking here of net increases to supply. Indeed, if you knock down 20 units of housing to build 25 unit

Of course that does not increase affordability. We're speaking here of net increases to supply. Indeed, if you knock down 20 units of housing to build 25 units of much more expensive housing, you probably don't increase affordability, at least in the short run. But those are fairly divorced from the reality of housing development.