Except that what he's worried about isn't really the issue. Look at Melee. Everyone has their own stage. Balanced right? Everyone's stages are equally difficult and you can get comparable times on all of them right? Hardly. The point of the target test has always been, and will always continue to be, how quickly one can finish a given map with a chosen character. The only difference now is that they're all playing the same map. Obviously Times will be different for different characters, but that's not the object here, as times were different before even when characters had "unique, balanced" maps to complete.
Another point: look at 1P mode. That was the same for every character, wasn't it? Everybody had to go through the same progression (well in Melee it was random) and do the same things, and for some characters it was possible to get higher scores than other characters. Every character had the same Race to the Finish map, right? Not everyone moves at the same speed, so somebody had to have the advantage, right? Well, now it will be the same with the target test. All characters play the same maps, and the differences in character fundamentals provide the differences in approach to said map. It's the same number of different challenges. More actually, because there are 5 possibilities for each character to choose from. When you factor in characters-stage combinations that's multiples more than Melee ever had, barring the Mixed-Up BTT that GameFAQs created using AR. And get this, when they did that, they discovered that many approaches became largely the same, because the levels were so specialized, so conducive to breaking the targets in a particular order. From the images we received, I'd say that things have been broadened, opened up a little, allowing for more creativity in sequencing and a better overall experience for players, with the added benefit of less work for developers. It's a win-win. It's just different from before.