At the moment I am not earning any interest on my bitcoins. Bitcoins had such a strong year in 2021, in my opinion there is no real need for interest on our coins. When making returns of 100% in a few months than we should be already happy with it. Crypto lending can offer us some good returns during our HODL periods, but we need to be aware that there are risks involved. 4 to 6% interest sounds nice at first, but when losing everything its devastating. It's another layer of risk we need to be comfortable with or not. Personally I am not looking for interest by lending out coins.
Another form of interest I had in the past was gambling. Before the recent bitcoin rally I used to gamble and play poker with my bitcoins. So every time I won money I withdraw using crypto currencies, and every time I lost money I covered the losses with fiat money.