Not a lot of difference in the end.
Very few Presidents were so controversial as to rally two-thirds of the Senate against them, so it remains very much a one-off. The Presidency may be weakened a trifle, but in peacetime it was relatively weak anyway, so not much change.
Note that only weeks later, seven southern states were readmitted under Republican governments, whose Senators would have overwhelmingly voted for conviction. So the Reps could easily have brought new articles of impeachment, and got Johnson out with no trouble at all, had they really wanted. They did not bother to do so. The whole business had been more of a temper tantrum than anything, and they had now got it out of their system.