I fully accept that, nowadays, Dylan's vocal range is limited and his enunciation is gruff. I can understand why some (many?) in his audience may go away disappointed, maybe even angry but, as I said before, there is an objective level to this and a subjective level.
I also accept that Dylan's performance is variable from show to show and, indeed, from song to song within a show. You will not get the sort of consistency that you experience with an MK show. Some in the audience may find that hard to take, too, but most Dylan fans go to shows knowing that in advance. Indeed, many Dylan fans go night after to night and travel vast distances to catch as many shows as possible, partly because there is variation in the set list and partly because they want to be there when, in their eyes and ears, he delivers.
As I think I said before, Dylan is not always an easy listening experience. You have to work at it and, in my view, it's harder now than it used to be.
Moving on, someone mentioned Dylan The Legend. Yes, there is an element of this. It is my personal view that, in 100 years time, say, people will still be listening to and analysing Dylan and his works. Those who attend his shows (even the more recent shows) will be telling their children and grandchildren (and the way the actuarial tables are going, perhaps even their great grandchildren) that they saw Bob Dylan once - and maybe saw him more than once! It is almost too glib to say that he changed popular music forever, that he showed that one can bring a wider range of words, thoughts, ideas, emotions to popular music and so on and so on. That's music journalism stuff and, in my opinion, the music critics so often review his new album in the light of its predecessor as much as on its own merits. And, it's all essentially opinion but there are some objective indicators, such as winning an Oscar and being invited to play before the (last) Pope. He may not sell albums in the huge quantities that others do but his albums can sell enough to get him pretty well up the charts even in the last few years. He can turn out albums of out-takes, alternate takes and the like (in The Bootleg Series releases) that other recording artists would love to have had as their frontline releases. While there is some dispute as to the actual number (depending on the criteria you use), he has approaching 50 albums to his own name. His body of work is simply prodigious.
Call him legendary if you wish. He's done as much as anyone performing today to deserve such an accolade. To some degree, he seems to treat it as irrelevant anyway, even a joke. I don't know if he has continued the practice at this year's shows but, for some years, he has had his tour manager open the show by reading out a summary of his life, taken from a newspaper review. You might find it funny and, I guess, a rather un-showbizzy way to announce a performer.