Is this actually dithering?

I have dabbled with some dithering algorithms and while this is way faster than my naive js implementations, this looks pretty bad

Is this what they use at schools before they hand it over to the printer? /j

I have to admit I don't think it's visually very appealing like that. It looks more like some sort of error/ glitch. Maybe my old Firefox does it weirdly?

It feels and looks like threshold-quantized Perlin rather than actual proper dithering. Cool stuff that said!

The image quality is so bad, I don't get it?