When I say practically, I mean it in the literal sense of the word.

Cars like the Veyron, Gallardo and R8 use engines of the V configuration, so it’s quite simple to route the propshaft for the front wheels past the crank casing because there’s enough space on either side.
I don’t quite know how you’d like to route the propshaft around a horizontally opposed boxer engine… You can’t route it around the block, you can’t send it over either. And because the whole idea of a boxer engine is to keep the centre of gravity low then passing the propshaft below the engine would result in a) having to mount the engine higher up in the bay (negating the whole idea behind the boxer application) or b) having the propshaft perilously close to the road.

No practical, mechanically elegant or economically viable way of doing it in my opinion.

Your historical reference is irrelevant and superfluous in this discussion.