No surprises there -- just more confusion. The new hardware was suppose to be for FSD only -- which is down the line -- and not for just for the "features" that were suppose to be rolled out soon. Now new hardware is needed for even adding some features? That makes no sense -- but even if true, how could Elon not know that? It sounds like an excuse that only gives rise to more confusion -- not less.
I don't see there being any discretion at all based on considerations. It's like saying someone is pregnant with no baby in their stomach and when you ask why they say that's because she's just a little bit pregnant. Words don't work that way. Either you're pregnant or you are not, and either the car Full Self Drives or it does not. There's no discretion or consideration involved, except with Tesla.
To be fair, Tesla always said EAP would be a four camera show and FSD an eight camera show. It is/was even in the configurator from the start. So there's that distinction, beyond the mere title of the package. Anything using more than four cameras would fall within FSD - as announced.
We know EAP uses the two front cameras (normal aka main and narrow) and plans are to use the side repeated cameras for blind-spot detection (automatic lane changes), so that's the four, I believe is widely expected.
Anything using the rest: B pillar cameras, rear-view camera or the front fisheye (I'm excluding standard features like rain detection and rear-view display) could IMO legitimately be consider an FSD feature.
Of course muddying all this is the fact that Tesla might well decide they need the front fisheye for some EAP related task, like speed-limit detection, though that could simply be a standard feature or implemented using the main front camera (similar FoV to AP1).
As for why Elon seems to have walked back on FSD features in August, I really doubt it had much to do with the hardware, the hardware is just another way of saying 3-6 more months perhaps? Originally FSD-only features were supposed to start rolling out 3-6 months from January 2017, so clearly announced on the original hardware...
My guess would be they need more time to improve accuracy and are still working on what to include in 9.0 and what not.