I personally think those are far better platforms for live streaming what's a bit of a community event. They mostly focus the running stream and have decent chat functionality. On Youtube I always feel like it's a random offline video with a borderline unusable afterthought chat and all the usual distractions on the side.
I always thought Twitch and Mixer were for watching other gamers play, not a couch chat. ESO and Forza seem to have no issues with livestreaming on YouTube but what do they know? If FD can't go to the "trouble" of taking a livestream and uploading it to YouTube, well that says a lot about FD, doesn't it?
Hardly matters to me I guess, I took apart my cockpit and deleted the game from my PC. I've put the game aside and won't bother with it until I see what FD's future commitment looks like, hence why I'm keen to hear from them. But I firmly believe a recording of the livestream should be on the FD YouTube channel, a channel that appears all but dead to anyone that subscribes to it. A single video 1:21 in length for the anniversary and then everything else is a year old or more, great marketing.