plus, if this guys looking to do a motor swap, everything is gonna be new anyways, assuming he does it right, so who cares?

The performance level on the Renesis will eclipse the FD over time.
Think back to how bad things were in '97 for the FD guys. That is where we are on the Renesis.
The engineering on the SE3P is far better than what went into the FD. It was just a beautiful car and very adept for its time.
It is mostly nostalgia and fear that keep the FD in the forefront of tuner technology as far as the 13b is concerned.

I'm not talking about just the engine. Think worn suspension, dried rubber everywhere, ripped/worn leather, broken knobs, thin paint, rattles, sticky locks, electrical problems, creaky hinges, carpet stains, etc, etc. And that doesn't even include the typical FD issues. But I guess that's fine if you're one to spend more time wrenching than driving.

I'm hoping to have a new RX long before a rebuild is required.

there are a couple of things in the renesis that are better, like the e-shaft and gears, but 1. those are interchangeable and 2. the 7 is a more capable platform, for everything but hauling groceries.
like I said, I like the 8, and I'm gonna get one, but if you're looking for performance the fd is the way to go.

so, you get polyurethane suspension bushings, a good set of coilovers, pull the leather out for aftermarket seats, or get the suede ones, keep it washed and waxed, it doesn't rattle, the locks are fine, haven't had any electrical problems, wd-40 the hinges (even though they have never once creaked) shampoo the carpet, and you're good. and then you have a good car, better than stock, that still looks new.

Gonna have to disagree having owned previous RXs and now the RX-8. The RX-8 is the superior chassis vs. the FD. It's stiffer (fact), and it has better brakes (imo). Yeah, the FD weighs less, but its advantage is around 150-250lbs.

What the FD offered from the factory was a stiffer suspension and a turbo. Both of those can be added to the RX-8.

What the FD really has going for it is instant gratification in OEM form as compared to the 8.

Uh, no. You need to dig a lot deeper. Everything on the Renesis is better.
Not necessarily more "adaptable", but stronger, lighter, better flowing and redundant.