I know VCE features correspond to GCN. But why should a consumer have to know this?
You're into hardware. You follow this things. A normal gamer shouldn't. For him R9 370X and R9 380X are cards from the same generation. That's why AMD named them like that, isn't it?
Of course Nvidia does the same thing, but they also have good documentation, so you can find the actual specs pretty easily.
I asked
@GoldenX whether his card offers a fairly basic encoding feature (lossless encoding). All he could tell me is that it offers the same features as cards built on the same GCN...
Game streamers are a niche group. Streaming (we could call it "real-time encoding/decoding") is not a niche activity. Many people do it. They will still benefit from a hardware encoder/decoder.