> when the technical distinction between those is pretty much non-existent

I think CEC support is still spotty and ARC (audio return channel) isn't supported at all in DP.

Well, CEC is a huge mess and barely works[1]. You're right on ARC and eARC. I'd rather DP had a better version of both, but that wouldn't happen.

[1]: If you have a stack that works, I'm happy for you, but trust you're just lucky to have a working combination.