To be fair, the octet as the byte has been dominant for decades. POSIX even has the definition “A byte is composed of a contiguous sequence of 8 bits.” I would wager many software engineers don't even know that a non-octet bytes were a thing, given that college CS curricula typically just teach a byte is 8 bits.
I found some search results about Texas Instruments' digital signal processors using 16-bit bytes, and came across this blogpost from 2017 talking about implementing 16-bit bytes in LLVM: https://embecosm.com/2017/04/18/non-8-bit-char-support-in-cl.... Not sure if they actually implemented it, but that was surprising to me that non octet bytes still exist, albeit in a very limited manner.
Do you know of any other uses for bytes that are not 8 bits?
> Do you know of any other uses for bytes that are not 8 bits?
For "bytes" as the term-of-art itself? Probably not. For "codes" or "words"? 5 bits are the standard in Baudot transmission (in teletype though). 6- and 7-bit words were the standards of the day for very old computers (ASCII is in itself a 7-bit code), especially on DEC-produced ones (https://rabbit.eng.miami.edu/info/decchars.html).