The RAM expansion pack for the N64 gave the developer different technical requirements to hit, but again I don't think anyone would consider that a different platform...
So on the one hand, you have accessories which change the way you interact - Wii Balance Board, Labo, the bongo drums, Kinnect and indeed the PSVR.
On the other you have ones that change or improve on the capabilities of the hardware - which would include the ram pack, Sega CD, N64DD etc.
In either scenario, I personally think it'd be silly to class them as their own platform, and I feel that trying to justify the decision to do so is just muddying the waters and, intentionally or otherwise, derailing the thread...
OK, my explanation wasn't perfect.
The RAM expansion pack for N64 didn't change the way of developping the game. It was truly accessory, every games could be played without it (except DK64 because they didn't find another way to resolve a bug, that's why the RAM expansion was free with this game).
VR is a new medium (even more than that), not just an accessory. It has its own games, its own accessories and a price in the same order of magnitude as other platforms.
We are talking about vg hardware sales in a context of fiscal year results. So I think I am perfectly in the subject by mentioning a device currently produced in the factory, delivered worldwide, related to video games and with its own lineup of a hundred titles from different developpers. That's not because we have a different vision that you can imply that I derail the thread. My question of "why no PSVR figures" is perfectly legitimate in this context.
The RAM expansion pack changed the way that the game were developed in terms of improving the resources available to the developer. In addition it Donkey Kong 64, it was also required by Majora's Mask & Perfect Dark, so a small but overall great list of exclusive games!
I guess we're just not going to agree on this. In my opinion to count as a platform it needs to function on it's own. All of the heavy lifting on PSVR is done by the PS4, so to say that PSVR can stand on it's own as platform smacks of counting the PS4 twice...
The specs that a dev has to work to for the PSVR is essentially the same as the base PS4/Pro, so all that's weighing in it's favour of being a separate platform is exclusive games, which again you could say for lots of accessories that I've already mentioned.
Likewise, if Nintendo release a VR mount for the switch, a la the samsung oculus headsets, I wouldn't count it as a platform either.
If you want to discuss Nintendo vs Sony gaming in the overall fiscal year, which can include accessories and games, then feel free to create a thread - but that's not what's being discussed here.
P.S. sorry for late response