I hold bitcoin directly, as well as put some in my retirement accounts (that don't hold bitcoin, but an ETF that claims to hold bitcoin.) If you were an institutional investor, you can't really go wrong with the funds. And if you are an individual investor, you can't go wrong with putting a little bit into your retirement accounts too. It's still best to hold bitcoin directly / physically / private keys, but a lot of people either have difficulty with that or don't understand enough to do it safely.