It's not going to happen. You can dream about it but there is no way that housing will be removed from current owners. Not only is that not going to happen but those with grandfathered homes will continue to keep their properties. Any new rules forthcoming will affect new home purchases and not those currently in existance.
The option of upgrading apartments is a good possibility given they're said in the past they would be looking into that and perhaps the implementation of instanced housing along side the current wards, 6.1 should be an interesting revelation as to whether or not they will be adding to the variety of housing options or simply adding more of the same.