Testing becomes immensely easier. One of my main gripes with requests was that it had a fantastic API but had very unpleasant internals that made it complicated

Testing becomes immensely easier. One of my main gripes with requests was that it had a fantastic API but had very unpleasant internals that made it complicated to test and mock http responses. If this is no longer the case, then this indeed is a fantastic change - looking forward to diving in soon.