I think he just meant using the argument that gg is better because of how much deeper it is, youd have to say that about bb compared to gg, too
This.
And unless Im missing something, BB has everything GG does, with the addition of the OD and burst systems and how it works, as well as how the CH system works (it seems to effect far more in BB in terms of combos and followups) along with a roster of characters who's mechanics seem to be far more complex on the whole than GG's individual character mechanics as well as BB seeming to have more emphasis on setup and trap scenarios for many many members meaning MU knowledge plays an even large roll, because some of the stuff is EXTREMELY specific in how you beat.. etc. Combos are also, by and large, longer and more detailed than GG.
Now, I'm no pro, but in terms of raw execution difficulty, I can sit down and do a solid amount of the stuff in GG and when you learn the timing and structure of one or two characters you can kinda swap around and pick up on other stuff fast.. but some (not all of course) of the stuff in BB is terrifying. Valk's wolf combos where he swaps back and forth, what's-his-fuck with the dp cancel insanity.. it's.. god.
It's interesting because I had heard that BB was GG's simpler sibling, and picked it up based on that.. and quickly learned that was not the case. My game notes for BB are four written pages. GG is 2. Character notes for Bb are about twice as long as GG.
Maybe I'm missing something and I'm all for being shown I'm wrong.. but BB.seems to have every mechanic GG does, with some it doesn't, even more ridiculous character specific rules and mechanics, far more sequences and combo routes and a steeper execution curve.
I played GG at, I'd say, low-average level after a week or two with the game. After a month with BB I just gave up and walked away.
Just for the record I think GG is the better game. It's probably the greatest anime fighter in existence. I was just commenting on depth = better is all.