+1. I just woke up like 10m before the video (and I'm a total grumpus for like 30-45m after I wake up). Initial reaction was: "... what. This is a jape, right? Uggggh", but as I woke up more and thought about it, ultimately, it was just disappointment. Definitely a bad pick IMO, but the music is amazing and I'm glad that's coming. I too am a huge fan of 3H (it was my GOTY last year), and even a pretty decent FE fan in general, but I do still ultimately think this wasn't the time for Byleth and they would have been better as DLC 6.
People definitely react differently in the moment and after they've had time to think and process it; in my case from just waking up, I was extra grumpy, and I can imagine a few people who may not have woken up on time and were petrified of spoilers, so they may have stayed up all night and are met with, again, what I feel is a rather disappointing end to FP1. Sakurai being extra troll-y when he was putting up the poster and gave us that look of "HEH, ANOTHER FE CHARACTER!" and unintentionally giving people the finger during his binary counting probably didn't help. Sothis even mentioned the "another swordsman" thing, so he knew how much of the community was going to feel about the pick anyway.
Again though, just disappointed. Bad pick, but at least we have 9 great tracks coming to the game (and 6 more characters)!
I really believe it's SE themselves choosing to limit what gets into SSBU.
Then why even give us the costume in Smash 4, the spirits in Ultimate, DQ content and returning SE costumes from 4? Honestly, it could just be a huge coincidence or everyone involved on decisions regarding FF is just an elitist who thinks they're above having their stuff in the "babby not-a-fighting game".
Or they could just be asking way too much and Nintendo/Sakurai rolled over for the returning Cloud content. Also how much of a prick could the DQ guy be considering we still got 8 songs from the series and 4 characters? Does this make the Persona guy a prick for giving us 1 character and 9 songs? How about the FE guys a prick for giving us the same character of both genders and also only 9 songs? I get it when it comes to FF, but not so much DQ.