And now you're failing to take quite a few other aspects into consideration here...
Have a look at this right here..

.
There's the car we're talking about that owns the solution..
You know why the solution works for THAT car?
The answer to that question is hinted in the following picture...
That little red MSPaint box represents something...
That something is, the cars subframe..
the cars subframe/steering section in relation to the engine, is very very aft...This is one of the reasons why subaru's are very nose heavy and have a tendency to understeer....
Meanwhile back on the car we all are waiting for...they've taken a big step to try and counter that notorious understeer..
They've...Brought the engine back in relation to the subframe..
to the naked eye, you can see there is quite a huge difference between the space allowed of the Legacy in relation to the front or easily identifiable pulley face of the engine..
Vs the very very small amount of room between the same points, and the pulley face of the BRZ's engine..
What does this mean? This means the structural mounting points are now in a different location in relation to the engine...
-pause for affect-
*Gasp*
This could be why the engines exhaust manifolds snake forward instead of come directly down and back.... Because in the midst of all of their crazy techno wizardry and "keeping the center of gravity as low as possibruu" by lowering the engine..well as low as possible..They removed the space they'd have to put the manifold "below the front of the crank area" as they did with the Legacy engine..
NOW there is a spot there i could see them putting a turbo, but it would catch quite a few other things on fire..
Lower you say?
But sir..There is no lower...
Now we return to this picture..
If you were to move the subframe foreward .... 1/2 a foot? Would that system work or would you now have a force inducted serpentine belt heater
...
Translation..
Legacy Turbo Fix = Not a Fix..
Result = Same situation we were in early..
Sorry if you guys had lots of debates and decisions on locations then came up with the bad bad bad answer of "legacy location"...but it don't work