I think the important difference is that Yasuo has a dash-then-channel.
Warwick, I think, is the only other character with a dash-then-channel ability.
Only these two don't have a choice after they use the button to not channel. They get stuck in place with no hope of movement (I think Warwick can cancel his ultimate with movement, actually, but when would you ever do that).
The safety net effect on it is more or less the same as Kai'Sa's Killer Instinct, except the player isn't given choice. It just automatically doesn't put you in stupid locations.
I do think it would be nice if the player decided where it put them, but I don't see an issue with the turret avoidance because it's basically just auto-giving you the thing that you would usually pick if you had a choice on where to end up.
Almost-- at least, I can't think of counterexamples-- every other ability that is 'slow' the way that Yasuo's Last Breath is has some other quality that makes that slowness not a huge impediment.
For example, Zed's Death Mark pops him into untargetability while he's going through its comparatively long animation, so he can't get shot by a turret anyway. Twisted Fate's Destiny / Gate has 5500 range on its recast. Karthus's Requiem is supported by his Death Defied and castable even if he's sitting in his fountain.
The closest abilities that I can think of are Neeko's Pop Blossom and Yuumi's Final Chapter, but Pop Blossom has very high base damage, 120% AP scaling, she can hide the wind-up, and has a stun-- in contrast I don't have enough experience seeing Yuumi to say much objective about it.
So while I do agree that Yasuo's ultimate isn't consistent in that regard, it's justifiable since the alternatives are so obviously awful.
Such as--
Making Last Breath Single target ► You remove team combo and one of the funnest moments (multiman Q->R).
Making the teleport point fixed ► Now the exact angle that you're at before ulting matters, which makes it very frustrating to use.
Making the teleport point cursor-dependent ► This seems to be the best, though it comes at cost of skill floor.