Why is this the end of mortgages many places in the U.S.?

Because flooding and fires ends insurance of various kinds and without U.S. insurance companies there can be no mortgages at least in those areas.

In California fires are ending mortgages and insurance when people can't get fire insurance (sometimes at ANY price) in other places mortgages end when people cannot get flood insurance (same problem). So, unless you are fairly rich soon you won't be able to own many places unless you want to rent a space for your motor home or trailer various places and I think we are going to see much more of this over time as well as a direct result of no fire or flood insurance many place here in the U.S.

So, if you don't own your home or property outright this can be a problem and it is still a problem if you can't get insurance and your home or land floods or your home or buildings burn down because you might not be ever able to replace these buildings without insurance.

So, this is why motor homes, Trailers and houseboats or yachts are going to become much much more popular than before over the next few centuries.

However, as winds increase all these things can blow away too unless you get them away from whatever winds in storms like Hurricanes, firestorms, etc before they occur. So, weather reports become vital if you are going to rely on motor homes, trailers, boats or yachts for your domicile permanently or temporarily. Because if you don't move them far enough away from heavy winds they are either going to be blown apart, flying through the air or washed up into buildings some place or worse.