Sorry, but "ugly" in the 1950s would have been somebody like Big Jay McNeely who intentionally distorted the sound of the horn. Rollins' tone then was certainly big, but I maintain that the perception of "ugliness" was due mainly to the articulation and phraseology than the tone itself, which was nothing if not multifacited as the "need" of the moment dictated and quite controlled. Always.
Intonation was sometimes an issue early on, as was occasional glitches in register leaps. But tone never was. Even the earliest Rollins, where he sounds like the horn can't handle his energy (not the other way around), is marked by a tone that is in no way "uncontrolled", and cetainly not "distorted". Certainly Illinois Jacquet's tone of the time was more "agressive", as were cats like Arnett Cobb et. al. But it was a time when certain elements within jazz were courting "refinement", which in some quarters meant "taking the edge off", which in yet some other quarters was extrapolated into equating certain types of directness with ugliness.
Which is all well and good, I suppose, but there's a fatal flaw there, and it's that the tenor (any instrument, really, but I speak from what I know) will have one kind of "ugliness" when it's not being played with control, and another one altogether when a cat knows how to play. In the latter case, accusations of "ugliness" reveal quite a bit about the accuser and little, if anything, about the object of the accusation. Because, let's face it - the number of people who will spend the time and energy it takes to learn to so something well in order to create intentional, unmitigated ugliness instead of some sort of personal vision of "truth and beauty" are few and far between.
Now, sometimes the truth hurts, as they say, and most folks do equate hurt with ugly, and nothing else. But that's their problem, isn't it...