Fly Antonov,
Actually, there are plenty of families who can simply make Rupert's payments until he's on his own feet. They don't lose much in the way of assets, except for some discretionary income or savings while they take over payments. I'll bet there is a lot of this going on already without the bank's knowledge.
The banks will keep lending, but they have already stopped doing it without security. They will be stricter about how much they lend and who they loan it to, but lending is what they do and they will keep at it.