You can currently get a 5%-interest savings account with some quite reputable firms (Morgan Stanley, Robinhood, Wealthfront). Those are effectively risk-free ways to earn more than 4%.
I think the 10-year treasury note rate underestimates things a bit. Maybe it's because there is an assumption priced in that interest rates will go down again?
But the point stands: right now, anything offering you more than 5% return must have some risk involved.