too soon for gen 4 remakes? gen 4 was a decade ago. they could have it next year and it'll be the same difference in time as gen 2 remakes and gen 3 remakes.
has anyone also considered that sun might be nx and moon might be 3ds? they did something similar with pokmeon mystery dungeon on the gba and ds.
It's less that it's too soon for Gen IV remakes, and more that releasing them on the 3DS when the NX is already out would just be weird.
I've considered the possibility that Gen VII is cross gen. It's not totally impossible, but I don't see it happening unless the 3DS's online features get a pretty big revamp. Despite NNID technically being supported for a while now, core services like the Friends List are still based on Friend Codes. As things stand right now, a game which bases it's online on NNIDs/Nintendo Accounts would lose out on OS integration on 3DS, which really wouldn't be a great scenario.
That said, even if they fix that, I just don't find it terribly likely in general. Cross gen would come at a pretty big cost, and it's on a Gen that is likely already somewhat rushed due to the timing. It seems quite likely that Sun and Moon spent a substantial amount or dev time as Z, since the current tie in media suggests that Sun and Moon weren't their original plan.