I think the extreme factory sponsorships are the problem.
Before them, privateers, clever men, and aftermarket parts companies built the cars and with them, a giant marketing campaign to sell parts. D1 is for all intents and purposes a live car magazine focused on the aftermarket IMO. Anybody can essentially duplicate much of the D1 line-up and at least to a significant degree. The point is, you can see an s15 running Dmax coilovers, save for month or two, go buy them for your s15 and drift the shit out of it. or that hks turbo kit, aftermarket knuckles, etc. perfect.
In FD, manufacturers are too involved. I could be wrong but I don't remember seeing any Nismo JGTC cars turned into drift cars or engines being donated in the way that a Toyota did w/ that Scion, Mopar w/ the Dodge, gm w/ the solstice, etc etc blah blah. Drifting in America is about selling cars - cars unrealistic for most of the fan base to even afford (or want). And then when you get them, you're stuck w/ a warranty that could be voided for drifting, heavy car payments, parts you can't get/make, etc. Brand new challangers, nascar powered tc's, vipers...wtf You don't open up a pontiac catalog and find aftermarket knuckles or gt30 turbo kits. So it sucks b/c its pointless marketing turning it into a boring sport. to me anyway.
I get excited watching s-chassis, 86's, w/e drifting b/c i can afford to buy one, modify it similarly, and go try the same thing. I don't get that excitement w/ fd. I see wanna-be rock stars with no personalities driving ridiculous cars I'll never afford on the same tracks against the same people over and over again.