A fifty-year building doesn't have to be a fifty-year investment. If you can build something for $1m and sign contracts that guarantee you $400k in rent in the next five years, and you think there's an very good chance that you'll be able to sell for >$600k, then building makes sense.
This is the case for a building where I know a tenant, except that I changed the sums.
Yeah they probably have done a ton of research. I look at the Surfside collapse and think, "nope, not buying in Miami."
As the author himself argues, in another tweet, and with unassailable logic:
You may not be aware of this, but housing isn't what's causing sea levels to rise.
Maybe they have done their research and I understand something I don't but I don't get it.