Wait, how is Akali "less mobile" now? Id argue its the same amount but slightly better.
Her only "real" mobility was her mini-dash in her shroud that let her hop over walls. Her Ultimate could only be used when targeting minions or champs. So if you were trying to run away from a fight you better get your Shroud jump over the wall right or you were screwed (you couldnt trinket hop with R)
now she has her mark-jump on her E with is basically a lee sin Q that also has a backdash attached to it (no sure yet if it lets you hop over walls yet )
And now her new ultimate doesnt require a target. Want to hop over 2 walls to either catch someone or run away? Why not, now you can do that while the also marking someone and dashing over to them ignoring all terrain.
If it turns out that you can also go past walls with the back-jump of her new E then she would be more a bit mobile than before.
In total she now has:
potential backwards jump hop (still not determined if wall hops are possible)
a lee sin mark-dash
two point and click dashes that no longer require a target
compared to:
shroud jump
3 dashes that required a target
so i really dont think she has "less" mobility. Id argue this new akali has more useful mobility but less stickiness