I'd challenge that its goal was aggressiveness. Testosterone is positively correlated with many extremely good things - energy, mood, better health, and much more. And it's inversely correlated similarly with depression, other forms of mental illness, persistent fatigue, and so on. Basically what men turn into as they age is, in large part, caused by testosterone reduction which naturally goes down as we age.

If there was some way to ensure the military had a higher end level of testosterone it would almost certainly be a very good idea. But the problem is that testosterone can't be supplemented like other things. When supplemented, your own body's production of t simply shuts down and doesn't necessarily return once the supplements end. So it creates a life-long dependency on testosterone injections, that are fairly expensive, at least in the US.

I think that aspect of it is why they most likely rolled this back. Not only do you have the issue of an army that's now dependent upon supplements for basic functioning, but you're going to have military retirees, who are already often left in a shit situation, now also dependent upon a relatively expensive treatment, forever.