This is perfect! So many possible applications that previously required external hardware like usb hubs and adapters for video in.
Now if its possible to make the output mirror the input while allowing for capture that would save on hdmi splitters while retaining the drm stuff hopefully. or using some parrot type protocol.
the applications i see for this are:
Ambilight like setups using led strips, bulbs, any controllable lighting via wled, hue etc. over wifi, ethernet, DMX, artnet, other ip lighting.
Running hyperion/hyperHDR from the HDMI in to the various devices over their respective networks. This can be used to immerse an environment with whatever the media is, movie, tv shows, video gaming, etc. within a single device.
It could also function as a backup recording and/or remote multiview for a security surveillance system again without having to add a splitter or exposing the system itself to the network/Internet by taking the hdmi out of such a multicamera system, recording it, and displaying the original input on screen...... could even use hyperion to input microphone input and motion to do stuff like flash lights or trigger some other automation if loud noises or motion are detected where/when they shouldn't be, like a 'red alert' Star trek type thing lol.
I run similar stuff on a rock64 1GB version 2.0 using USB to HDMI, it runs great, no lag that I've noticed. even had to set a small lag in the control output so as to not cause eye strain. Phillips came up with that as they said their experience was that the slower changes to the colorleds behind the TV reflecting on the wall could ease into the new scenes colors and brightness a few milliseconds and with a limited brightness range so as to make viewing fast changing scenes not cause the iris of our eyes to have to adjust so much and rapidly which leads to eye fatigue. Though the system can handle instant changes if that's what you want.
Works well for mapping music too like the hue sync spotify thing.