I have just submitted this feedback to Apple…
I recently updated my iPhone SE to 13.2.1 and have found that shuffle songs no longer works when the phone is connected to my car via Bluetooth. I have nearly always selected Library/Songs/Shuffle when I start a journey but after the update it starts playing my albums in alphabetical order. There are only so many times I can stand to listen to Abba’s The Winner Takes All
Now I have to remember to select shuffle songs on the phone before it connects to the car.
There is a slight chance that a recent service of my car included a software update that changed the way that bluetooth works but this is unlikely as I am using the iPhone screen for the selection.
[Additional info: (selection done before I drive away, of course - it is illegal to touch the screen or hold a phone while driving in Australia!). The car controls only allow pause/play, skip track and volume adjustment so I don’t select songs to play using the car controls]