IIRC PDP-11 was a 16 bit word machine with an 8-bit byte. Maybe you remember PDP-10 with 4x9=36 bit words?
Basic stuff like SIMD, SIMT, without requiring users to go beyond language extensions, something that any programming language can offer in similar capacity?
> something that any programming language can offer in similar capacity?
By your measure a lot of other languages don't offer anything to begin with, because they do not have a standard at all, only a reference implementation.