Former NFL player Michael Oher claimed that he was never legally adopted

My thoughts I never really care about his story. Didn't even watch the movie or watched any documentary of his life. His life's story is like 10 years old or something. Don't know but if he is saying this now, why he didn't say it then?
When the movie came out, he was just starting his career with the Ravens.
It’s entirely possible he didn’t want to ruin his career/or didn’t want retaliation from Tuohys while he was playing.