Even the simplest scene with 1 quad cannot keep stable 60 fps! Help!

I
am at the end of my options. There is something wrong either with the
Oculus Plugin or with my Oculus Go. My game used to run with stable FPS,
but now even a clean new project and the simplest scene with a quad
dips below 60 fps.

Here is the video: https://www.youtube.com/watch?v=kUXFFXvLn8I&feature=youtu.be

Here is the blank new Unity project https://drive.google.com/file/d/1DF6mTinvetqmJqxpizJCaPGsYgoj5MEJ/view?usp=sharing

And here is the apk https://drive.google.com/file/d/1TjT9H_PW1e-X7mz26KctAskZ12RZADxz/view?usp=sharing

Can you someone confirm they also get that performance on their Oculus Go?