VideoStream uses picamera wrongly

[kpoman]

VideoStream is picking up the picamera even if I say usePiCamera=False ... This happens when I do have a picamera but no usb cam connected. I would expect some exception or a None capture object, but it still creates a picamera one.
My environment:

(venv) ubuntu@rpi3:~/Dev/identific-ai$ python --version
Python 3.9.5
(venv) ubuntu@rpi3:~/Dev/identific-ai$ pip freeze
click==8.0.1
dlib==19.22.0
imagezmq==1.1.1
imutils==0.5.4
numpy==1.21.0
opencv-python==4.5.3.56
pafy==0.5.5
pyzmq==22.1.0
Werkzeug==2.0.1
youtube-dl==2021.6.6
(venv) ubuntu@rpi3:~/Dev/identific-ai$ uname -a
Linux rpi3 5.11.0-1015-raspi #16-Ubuntu SMP PREEMPT Wed Jul 14 11:04:58 UTC 2021 aarch64 aarch64 aarch64 GNU/Linux
(venv) ubuntu@rpi3:~/Dev/identific-ai$