Not blind but I just want to put out there that low literacy in the blind community is largely due to lack of Braille teachers and parental negligence.

Level of literacy i think depends on many factors and can't be generalized so easily. Depends on country/region, access to braille teacher/school later on to books/braille display and similar technology if even available if even braille is needed: many especially younger ones are preferring screenreader/smartphone content/internet/ebooks or audiobooks they're way faster.

I was later on legally blind as teen, no access to anyone who knew braille altrough i was in low vision and blind local group, was once on 2 week schooling for blind/low vision teens where was few hours braille alphabet reading and writing with slate. I preferred much more audiobooks/screenreader/Zoomtext MagReader or electronic magnifier I was as fast or faster as proper vision. I was bookworm, now with smartphone and apps like Kindle or MoonReader (reads aloud many formats ePub even pdf) i read more than average citizen of my country.

Since last year i got OrCam MyEye and EnvisionGlasses so even more books, magazines are now available for me it's great for school and leisure so much more comfortable than electronic magnifier or holding smartphone especially on the go so number of books i read jumped up last time especially due more free time due pandemic.

This is actually an interesting question for me because I'm a semi-professional voice actor. I use either braille or speech output to cold read. I actually find speech output better. I find I read braille too slowly to be able to compatently use it for reading out loud. Speech output on the other hand has its own challenges: needing to narrate or actually act what I'm hearing" Generally I find my reading comprehension is a little higher with braille, but I much prefer speech. As a writer also though, I do like to know how text is formatted and words are spelled.

It takes me about an hour to read 20 pages of your average paperback novel.

I'm not reading text that small. I read on my kindle and enlarge it, but for putting it in the context of "how much content in X amount of time" it works out to about that.

My biggest problem these days though is that I can't read for long periods of time anymore. I used to be able to sit all day and read a novel. Now I need to take a short break every 20-30 minutes and can't read for more than a couple of hours without needing to stop and take a longer break (or a nap - eye strain is surprisingly tiring).

My dad got blind later in life and he chose not to learn Braille. He got really good with screen readers and started listening to lectures and audio books instead. I think it was much easier and faster for him to read and learn

I have screen reader set to 100% rate, so I read quick enough to get a headache.

My braille is still very slow, but improving. My print used to be faster, but my vision is so poor now, things have to be enlarged so much, and my eye gets worn out that it's quite slow now. Audio is the easiest currently, but I think that's only a supplement and not a substitute: I'm going to keep slogging away at braille until I get faster.

I read extra large font and braille. “Large print” books are too small to read more than a couple minutes without significant eye strain. Letters have to be at least 1/4” high. I can read an average paperback in 6 hours. I don’t have any idea how many wpm that is. I started learning Braille in May and it takes me Forever to read the same size book in Braille, but I’m getting faster every day.

not very fast, I imagine maybe 20 25 print pages in an hour I don't know it's been a while since I checked. This estimate was based on cutting the number of Braille pages I read cut in half. I read with Braille books, with my Refreshable Braille Display screen, and around 50% of the time also listen to books.

I was born blind. I started Braille at school but have issues with finger sensitivity and dexterity due to premature birth, muscular development, fine motor skills and all that irritating stuff.
I grew up in the 90s, when the only type of speech synthesis I could use was formant based (google for speech samples of Keynote, DECtalk, Doubletalk, Eloquence and the original Orpheus for an idea of that).

My leisure-reading speeds (as of June 2020) are:
Braille, 114 wpm.
Ebooks in synthetic audio, 646 WPM.
Neurotypical audiobooks, 2.5x realtime.

I prefer synthetically read ebooks, then Braille, and will only listen to normal audiobooks if I have no choice.
I occasionally hot-swap between TTS and Braille if I want to rest my ears after a long day at work for example with much noise all day, or if I am in a particularly loud environment and can't listen (yes, I have been known to sneak a chapter in a nightclub).

I think my Braille reading speed is like 150 WPM. That was at full-speed, cannot go any faster without making mistakes, and I would never read that fast normally.