Just to address the bolded part...
If one is comparing powers from classes against each other, they really are, factually, quite different. As pointed out above, Come and Get it is very different from Blinding Barrage is very different from Powerful Warning is very different from Verdant Retaliation, etc. etc.
Within a class, yes, some powers were mere upgrades of other ones, and some effects of some powers were a tiny bonus because they instead did more damage. I can see those being similar...but what would make no sense at all is to say "Too similar for me to enjoy" but then do literally the same thing ("I attack recklessly!") over and over again and not find that "too similar to enjoy."
Non-casters in 5e have had their options made much more similar to each other than they ever did in 4e. Maybe barbarian powers in 4e weren't differentiated enough, but they were more differentiated than ever before or since.
Perception can sometimes be funny.
Have you ever walked into a store, found an aisle with three dozen slightly different variants on the theme of "shampoo", and felt like you'd really rather just have
shampoo and be done with it? Like, even though the differences between the shampoo products are admittedly real, they are not as big a deal as the people trying to sell you the shampoo would like you to believe, and not worth your time and energy trying to sort through?
Or maybe you've never had that experience, and it makes no sense at all to you. So what? What does saying "That makes no sense at all!" accomplish? When the observable evidence makes no sense according to your premises, you can either get frustrated and scream and shout, or you can face up to the reality that something is wrong with your premises. So if people react one way to 4E and a different way to 5E, but this makes no sense because they're supposedly doing the same thing in both editions, then
it's wrong to think they're doing the same thing in both editions. Some variable must be different. The constructive thing to do is to figure out what that might be. If I were you, I would start by exploring this "illusion of choice" phenomenon; it seems a likely suspect.
But, just a warning... If you or anybody else are gearing up to argue that that people are mistaken to regard 4E as offering mere "illusion of choice" because 4E's choices are real and meaningful, then:
Stop. You have missed the point of this post entirely. Meditate further on the question
"What does saying this accomplish?", delete whatever it was you were composing, and try again.
If you
did get the point of this post, I'm sorry to have patronized you like that. But I felt it was necessary for the sake of absolute clarity.