Some of those don't make much sense, though. Darius is supposed to be extremely kiteable in exchange for his up close dueling potential, Kalista is one of the mobile champions people want to catch and smash, Ori is long ranged with a speed boost, so I suppose she could be debated, Riven is a mobile champ(Jumping over walls, dashing away with a shield, etc.) Not sure why Karthus is there, unless you mean his ult, which would require that they be caught and put to near death health first. Ekko is a mobile champ that people are complaining about, so is LB, Ahri is pretty damn mobile herself.
I get your point, or at least I think I do: "Mobility isn't as much of an issue as people make it out to be.", but some of your examples make no sense.
That said, I do agree that other than a few problem children that are getting worked on (The breaking of Kalista's ankles was a nice touch for a lot of people) it's not that big of an issue. If I misunderstood, please tell me what you meant, I'd be happy to understand it a bit better.