Personally I don't think it does. Surviving things with only 1 HP just doesn't seem like tanking, because if you would've taken 1 damage before, just 1, you'd be dead. And to answer your question, there's nothing we need to give up in exchange for being the fastest. Because like you said, Titan Skating was probably very unintentional. Here's a difference between strikers and gunslingers. By repeatedly tapping the X or A button, Titans are able to move very quickly in one lateral direction, but not quickly enough for them to become a hard target. However, a Hunter's double jump can be used to disorient targets by changing direction suddenly mid air. There's a difference in being the most agile and fastest, and hunters do not have to give anything up. You could argue that they give up armor, but like the point I've been trying so hard to make, the differences between having low and high armor is so miniscule that it really doesn't matter.

Titans have shorter melee range. They're also the "fastest" in a straight line. Hunters are more agile. They have quicker lateral movement, something that comes in handy when trying to avoid bullets.