Bluetooth radios generally operate at an order of magnitude lower power than wifi or cellular radios, especially in LE mode.

Really the Bluetooth protocol is mostly just a ultra low power 802.11. It has more channels but they are thinner bands are only 1-2 Mbit (depending on classic or LE mode).

That being said its not really a bandwidth limitation. One device can use multiple channels and thus you can easily get, say, the 6 Mbit that DVD quality PCM takes up.

It is more that being so low power means bluetooth gets pummeled with a lot of inference. This isn't much of a problem if you are using one channel and alternating to avoid hot regions but the 2.4 band is super congested. Trying to drive constant 6+ Mbit through Bluetooth losslessly would take way more power than most Bluetooth devices are capable of or willing to spend to accomplish it.