At least one of those big banks notoriously pays interest asymptotic to zero
if you (or a friend)have a stock brokerage account ask your broker what brokered CD’s are available..Wells Fargo, Morgan Stanley and Goldman Sachs as well as many others have CD’s available through brokers that are not advertised...some are one year or 18 months and just over 5%.....
brokered cd’s:
https://www.investopedia.com/terms/b/brokered-cd.asp