I too would very much like be interested by it! I bought a USB-C-to-HDMI cable, plugged a monitor, and everything worked well. I thought that using this + and USB DAC for audio, I could directly turn my Helios64 NAS into a media center.
Unfortunately I tried tried the RK3399 legacy multimedia framework (I just did sudo apt install media-buster-legacy-rk3399 --install-recommends ; I thought no harm could happen by just installing a package) and now my NAS won't boot (U-boot stops after "starting kernel").
I don't remember what kernel I installed, possibly this was not the legacy kernel. Thus, I would happily use some advice on how to unbrick my system -- and also upvote this vote, it would be terrific if the feature was installed in the default images or if there was an easy way to install them!