Well, my HTPC has a Ryzen 3 CPU in it, so IGP is not an option. I currently have a 1030 in it, which doesn't do 4K 60 Hz with full 8-bit colour and no chroma subsampling as its output is only HDMI 1.4, I think.
I also happen to have a 4th gen Core i7 with a mini-ITX board, but the HD Graphics 4400 is even worse in the decode / video output department than the 1030 or the 6400, so it's a no-go.
Low profile variants of the 1650 are pretty much non-existent, as I said. The ones I occasionally find on ebay sell for about 300 quid. Expensive AF, if you ask me.
So yeah, a 6400 for 160 USD that is actually available, seems like a winner to me. Its closest (only?) competitor on the green side is the 100-quid GT 1030 which doesn't come anywhere near 1650 level.