It's interesting to speculate about who he is, but I suspect there isn't any satisfying canonical answer (TLDR: I don't think he is a previous version of Morpheus). I'll approach this by first surveying the sources I'm aware of (my blind spot includes all of the games, and the handful of comics excluded from volumes 1 and 2) which might have context clues, and then my own (admittedly speculative) reasoning about where they point. (Aside: I greatly appreciate comments correcting any fact errors I make here.)
Survey of potential sources of context:
- The blind man is credited as Steve Dodd (Wikipedia & IMDB), an aboriginal actor with a career spanning several decades.
- AFAIR its provenance is unclear (if anyone knows its provenance, please set me straight!), but the early 1996 script has a very different "version" of this scene set in a bar. The scene has named characters Rex and Mojo, and an unnamed bar-tender. There's no obvious equivalent of the blind man. I don't see a PDF version I can link to a page on, but you can search "EXT. BAR (MATRIX) - DAY" to find the beginning of this sequence.
- In scene 76 (p66) of the 1998 numbered shooting script, there's not much detail about the blind man:
Morpheus nods to a blind man who nods back. An elevator opens and Neo follows Morpheus inside. (This description is the same as in the final draft shooting script included in The Art of the Matrix)
- The storyboards in The Art of the Matrix skip right on over this scene.
- None of the commentary tracks pay any attention to this scene.
- The live-chat transcript originally from the Warner Brothers website doesn't have any obvious commentary on the blind man. This is relevant because the chat transcript has notes that indicate the movie was playing during the chat, which, AFAIK, makes it the closest thing we actually have to a commentary track by the Wachowski's on The Matrix. The Wachowski's do inject a number of unprompted comments as the film progresses, including one moments later when Gloria Foster appears as The Oracle.
With the information we have up to that point, the fact that the blind man nods back at Morpheus (and that the script agrees he is blind) seems to limit "what" he can be to: a prospect, or an unplugged human hacker. Later in the trilogy we can add the possibility that he's a program. I can think of a few more options, but they're all increasingly speculative. Anyways:
- A prospect seems unlikely. If there were prospects this old, I don't know why anyone would make a big deal out of Neo's age. (FWIW: the 1996 script makes an even bigger deal of his age)
- A hacker seems plausible, but it seems risky to hang out near the oracle (unless perhaps he's also escorting a prospect--but it seems like he'd wait inside as Morpheus does). The fact that Morpheus brings a full crew in to secure the mission seems suggest it is a big risk (but we don't see any indication another full crew is around). The fact that they leave Mouse alone (but heavily armed) to guard the hard-line further suggests that they think most of the risk is either in transit, or in visiting the oracle.
- A program seems plausible, but I'm not sure he's a guardian like Seraph. In the third film, the Oracle says Seraph has been her guardian for years. The exterior of the building they're in (described in scene 75 in the shooting script) is described as:
Tenement-like and vast, it is the kind of place where people can disappear.
I don't think the blind man is a previous version of Morpheus for a few (thin) reasons:
- None of the sources go into any detail about this character.
- I can't think of any obviously-canonical in-universe causal mechanism that would support something like a previous version of Morpheus. I don't recall anything that clarifies whether the matrix is effectively re-loaded with the same original set of humans (restore from backup), or if the people who populate a given round are just everyone plugged in at the end of the previous round. The Architect's monitors are a hint for the former, but I guess Neo could be the only direct copy. In any case:
- If it's the first, Morpheus would also be the same in each round.
- If it's the second, any previous Morpheus is presumably destroyed along with Zion
- Body of work and interviews give me the impression that the Wachowski's are fairly thoughtful about casting decisions. I may be projecting too much back onto who they were over 20 years ago, but I have a hard time squaring that impression with the idea that they would hire a famous aboriginal actor to play the "previous version" of a character they hired an African-American actor to play.
It's not a good replacement for a satisfying canonical answer, but since interviews also give me the impression that they're pretty good/eclectic cinema nerds, I think it's worth considering that this may be an easter-egg homage--a literal head nod--to Steve Dodd.