The long term bond rates went that low but mortgages didn't quite make it that low. Fell as low as about 2% depending on the type of loan. They may have made it to 1% if their low interest rate climate lasted longer.
This article only goes till '99, don't know if they fell a little more after that. Their bond market sold off heavily so rates are higher now.
As to your other questions, their banks have not done well but don't know how much that has do with their lending rates. It's changing rates that effect banks more than low rates. They weren't paying their depositers anything.
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