Undoubtedly, and understandably, 2K's had bigger fish to fry the last few years than concentrating on classic team art. I don't fault them, though I wish it wasn't so.
That said, with the mention of some new classic teams coming our way this year, hopefully that falls in line with a slight re-commitment to realism with these squads, at least in terms of getting some likenesses up to par.
I'd suppose this thread would be a good place for my last-gen/current-gen Bill Russell comparison photos:
Last gen:
Current gen: