Having read a few papers I found on Google Scholar, I've realized it is much more complicated than that, and a lot less understood than people like to think. Of course, it is possible that hormones are the only advantage, but there seems to be more to it than that, considering the other posts in here by people equally as adamant as you are that there are important size, build and bone structure issues involved. Your word isn't enough to refute that. It's still being debated in the scientific community, which says a lot more than any non-expert could.
All of that being said, I hope that whether they find an advantage or not, they are able to solve the problem (the problem being the appearance of an advantage) in athletic leagues to the mutual satisfaction of everyone affected. Trans individuals deserve to be able to participate without this shadow hanging over their heads. If I was trans, I would want to know whether or not I had an unfair advantage, and I would want other people to know. If you're right, more research and discussion will only disprove the advantage, which will only be fantastic for the trans community.
All of that being said, I hope that whether they find an advantage or not, they are able to solve the problem (the problem being the appearance of an advantage) in athletic leagues to the mutual satisfaction of everyone affected. Trans individuals deserve to be able to participate without this shadow hanging over their heads. If I was trans, I would want to know whether or not I had an unfair advantage, and I would want other people to know. If you're right, more research and discussion will only disprove the advantage, which will only be fantastic for the trans community.