That’s the problem they are just carrying on,
Typically home owners sell and move-up/relocate/move down or just move every 5 years.
The underwaters are STUCK!! (and yes most will ride it out)
These are also typically the ones who carry little equity compared to long term home holders.
These transfers generated approximately 20% of the economic activity of our economy,
IT’s BROKEN, RE is BROKEN, the cycle is broken.
There is no easy way to replace it.

In this case you have few choices
1) Find a magical economy Job creator (not easy)
2) Inflate (this is what we typically do but it seems that it is something we have politically made impossible).
3) wait maybe another 5 to 15 years for home owners to pay down the debt or die.
Well enjoy !!