I think that it's a moot point. It depends on the audience. The only point which I think really matters for some is encoding. The other points are, I think, only relevant to a tiny minority. Sure, they're bonus points, but they're not that important.the 1650 has much more & better features (NVENC/NVDEC, x16 bus, 3 displayouts, OC support) than this tho, it's like leagues above the 6400
It's true that low profile cards are also only relevant for a minority of people, but AusWolf is right in that the 6400 is important for the low profile market because of its good price. Few if any people in that market will pay £100 more for a used card of similar performance just because it supports encoding.
By the way, if you're counting minor features, the 6400 has HDMI 2.1, making it "leagues above" the 1650's HDMI 2.0.