Johnson could not tame Marvin Hart in 1905. Major red flag. This was a high stakes match with the winner having a good chance to fight Jeffries next. Hart won. Jeffries said he would fight Hart if the public interest was there. It was not. Jeffries was above Hart on the level that Wlad or Vitlai is above anyone else today
I agree there was a lot at stake for Johnson. Now, I don't think there was any chance Jeffries was going to meet Johnson, even if Johnson had won decisively. Jeffries probably would have met Hart if Hart had won decisively; anything else, Jeffries was retiring. Even so, the Hart fight was very important for Johnson: a solid Johnson win would have retired Jeffries and established Johnson as the obvious #1 contender. It would have been hard to justify denying Johnson a crack at the title.
Most of what I've read of Hart-Johnson inclines me to believe it was really either a draw or a non-dominant Johnson victory; I think Hart got a gift. Johnson got a bit screwed, but also screwed himself somewhat by not putting out.