Because there is no decent footage of him available. Only grainy, unclear footage from which you can barely draw any conclusion without using your imagination a lot to fill in the blanks.
You are dead wrong there. Langford could de everything. He could swarm his oponents, he could outbox or counter them, He could dance up on his toes and outflank them. If you want a fighter without a significant flaw in his game then he is a good start.
The only film I saw the Flynn fight. And it seem like a brawling affair until Flynn was knockout. Of couse the film was super fast lol. I didnt see him oux Flynn, he out slug him in that fight.
Against Flyn it made sense to use a pressure style because Flyn himself was not a big fighter. Against larger fighters like Wills Langford used to dance around them darting into and out of range. You can see this style demonstrated in the footage with Lang.