I’ve started to use the floating thumb technique today. It is working fairly well. One issue I still have is, that I don’t know where and how to place the thumb when playing the E string.
On a side note: I’m a bit disturbed by the fact that all BassBuzz lesson videos by Josh are showing the picking technique with the elbow behind the guitar body and the bent wrist of 90° (or more). This sets a bad example and safe technique is not addressed in the beginners lessons. I’m not saying that one will develop any issues with that bent wrist technique, but there is a realistic chance and so it should be at least pointed out that there are alternative techniques and why one would use them. But in many videos I just see this technique as the default that is taught to everyone.
While searching for some more examples of the floating thumb technique, I stumbled across Adam Neely’s old video about save technique that goes into detail of how to play with a straight wrist.