Bluetooth doesn't turn on

Solution 1:

I have the same problem in Ubuntu 20.04 (with kernel 5.11.12). I have something that works for me everytime I want to use the bluetooth:

1. Turn the bluetooth on on that setting's screen you are showing (eventhough it still says that its off, just click on the 'on' toggle on the top right corner).
2. While its on, run the commands you just said:

sudo rmmod btusb
sleep 1
sudo modprobe btusb

Then I can start to see all the available bluetooth devices and connect to them (I use a playstation 3 controller via bluetooth and haven't had a problem with the connection)

The downside is that everytime I turn the bluetooth off or restart the computer, I have to repeat the steps 1 and 2. I'm still looking for a more stable solution.

I also tried blueman but it didn't solve the issue.

I hope we can find a more permanent solution soon.