I don't often come to these forums, I mostly visit The Fwoosh, where we talk to MS fans and look at polls, and the MS Facebook group, where people who are invested in the line post their own polls and opinions. But maybe I need to start coming here, especially if incorrect info is going to circulate, and people are going to make assumptions about the MS line, among others.
Shrink button or no shrink button, if ML were to release a similar, smaller version of our Beta Ray Bill, or we were to release a similar, larger Sasquatch, I don't think anyone, including licensors, manufacturers AND collectors, would be happy. You MIGHT be one of those people who make money scanning and shrinking (or enlarging) other companies' heads (which IMHO pushes the definition of customizing), but in the professional world that kind of swiping is frowned on. Besides, this one is specifically based on his mini-series look, and would not work as a classic BRB, so you'd have TWO Mohawk Bills, and reaction to the mohawk is already mixed.
And MS is not an ML-completing toy line. While we make PLENTY of larger figures, we will never focus on them, because we are our own scale and we have our own collectors. We need to make regular-sized characters as well. We will likely NOT make another Abomination. I doubt Sasquatch will top our list any time soon. But Titanium Man was a hit, and I think BRB will be a hit as well.