Eh, I don't like 2D scrolling, it is a lot more of a pain then 1D scrolling - so I think it's a valid problem to try and resolve. That said I also think PDFs are just conceptually broken when it comes to mobile devices - you specifically don't want single format files on that device and, often times, you don't need to consume them on mobile.
It seems to work well to me so I don't know what you mean by conceptually broken or single format files. Having a single file that you can zoom in and out on was one of the original multi-touch demos in the TED talk, years before the iphone.
I'm also not sure why they are different from anything else when it comes to 'needing to consume them on mobile'.
I agree, my 12.9" touch screen is the best device for reading PDFs I could imagine. A ReMarkable is at least as good for black and white (I've tried it) but a lot of PDFs are full color.
PDF on a phone is unremitting pain. I'd rather muddle through on a laptop. I'll give this this a shot, it might help, and it can't hurt, since it's just a button you can push that says "make this thing legible, maybe".