First off: We're not a 100% certain on how the whole system is going to work since that information hasnt been released yet.

Second: When someone relocates their home the amount of open housing plots stays the same, so that feature isnt preventing you from owing your first house ever, the general shortage of housing along with the fact that the initial buying of houses will be FC-only for a while, is.

Third: Until tomorrow those changes arent in effect yet, so obviously til now you've seen people flip and resell houses. Because til the servers went down for maintance this morning, nothing had changed yet.

The RNG timer is going to hurt house flippers, not new players - unless ofc that new player was relaying on someone flipping or giving up their house...
The housing system isnt perfect, but those are steps into the right direction. Relocating a plot will automatically free up another one - so thats not preventing you from getting a house either.