The #1 advantage of transverse FWD architecture is not in the interior packaging (still advantages) or safety (almost no advantages) or slick roads driveability (almost no advantages with modern TCS and stability control)...it is in production efficiency that is not lost with AWD.

Modern cars are mostly a passenger cell, front subframe, rear subframe and then body panels hung off these assemblies. If your entire front subframe comes with engine, transmission, driveshafts,front suspension, steering, cooling, AC, etc all attached from the supplier (internal or external) then after the body is dipped and painted, the entire assemble is insterted with only about five quick-connect hose connections, 4 bolts (10 if the struts have to be bolted) and two wiring harness to deal with.

If the car is offered with AWD the tranny will normally have a stub splined output shaft so the front subframe process changes none. The rear subframe adds one step in that the prop-shaft has to slide onto those splines as it is raised...and maybe and extra wiring harness.

The process is actually pretty slick but it does not mean I want the driving dynamics of a FWD car. I will say this after working on three different FWD endurance racers...you learn quickly that just dropping that subframe is about the only way to do a lot of stuff but it is not nearly as hard as it seems it would be. As with most things, once you know how it was assembled, disassembly is not that bad.