People are self replicating, houses are not. Give them sufficient food and time, and there will soon be too many of them.

It would be more accurate to say 'People are more emotionally attached to people than houses'.

There are more people born each day (400,000 a day) than there are houses built each day (4,657 a day). So I'd say no, houses are harder to replace than people.

You can replace a house to the extent that the old residents are happy with the new house. You can't really replace a deceased family member with someone else.

I'm pretty sure more than 1.7M houses get built every year worldwide.

If you count "dwellings" or "housing units" then surely yes. Many/most of those will be apartments and multi-tenant buildings rather than houses per se.

And then there are all the "houses" built from salvaged materials in poor countries. Not sure if you'd want to count those. A person living in such a structure would still be considered homeless in many places.

Where did you get these numbers?