I think it's just basic macro. Interest rates are low, it's easy to get loans. Interest rates are high, and it's hard. Excessively low, and maybe people make 20

I think it's just basic macro. Interest rates are low, it's easy to get loans. Interest rates are high, and it's hard. Excessively low, and maybe people make 20-30 year commitments that they aren't ready for. Like, would we all be better off if maybe student loans were a little tougher to get? Also, lowering rates speeds up the economy a bit. It's probably better to run a little high, so interest rates can be dropped a little when bad things happen; that'll goose the economy, and power through small rough patches.