Seagull
Thank you for interesting idea!
I immediately tried tracing paper and have to say its effect is weak, sonewhere near or even less than my current set of screen filters, and I even don't see screen clearly but still feel its brightness.
But I have huge doubts about whether any tracing paper can depolarize the light completely when the slightest details of screen are visible.
Have you ever seen the screen without polarizing film? I suppose every screen is completely white, including oled's. No film means no image.
Below is what i found about the topic in some textbook. It is google translated from russian, again.
I believe you can get some depolarizing effect but not a total removal. This is why it makes sense to try different screen overlays or better to repolarize the light completely.

"Multiple light scattering by wax paper can be demonstrated as follows. Place the paper on the page of the book. With this, you can easily see black letters. If the paper is lifted one or two centimeters above the page, the letters will blur and become practically indistinguishable. To understand this example, assume that black light is falling on your eye from the letter, which is scattered by wax paper. Here is another experiment illustrating the scattering of light by wax paper. Take a flashlight and direct its beam through the wax paper to a surface. Gradually removing the fountain from the paper, observe the size of the light spot formed by the light that has passed through the paper."

    dev