A number of very large brokerages have short-term largely treasury accounts returning in the 4-5% range right now. I wouldn't toss all my money there but it seems like a pretty good place to park cash for the next year or two until rates drop.
Bond yields can only be compared apples to apples at similar durations and at similar credit risks (which FDIC insurance normalizes).
5.78% for 4 weeks
5.30% for 8 weeks
5.16% for 13 weeks
5.28% for 17 weeks
5.18% for 26 weeks
4.98% for 52 weeks
One of the many baffling parts of the economy currently.
Of course, this is only a great deal if the money is taxed at a very low rate and your horizon is very, very long.