For perspective the "Banker's Ditty" used to be: pay 3% on deposits, lend at 6%, and you're on the golf course by 3pm.

Prior to 2008 it was pretty normal for savings accounts to pay something like 2-4%, more if you locked up money in a CD or something for a few years. Mortgages were in the 6-8% range, less if you got an ARM or something. Borrowing money at 8-10% if you had poor credit or something was common.

This was relatively normal for many decades. Many lost this perspective after 2008 and the slow-motion intervention since then.

If savings account rates get to something like 7-8% then most people have little reason to invest their money and the economy stagnates. The central banks try to keep this in the sweet spot of around 2-4%.