Why did Veronica Roth do a u-turn on her stance in white-washing when it came to her own movie?

Authors seldom have control over things like casting (although Cassandra Clare did spend an awful lot of time bragging about her creative control of the TMI movie until it flopped and she did a whole lot of hand-wringing). However, for Roth to go from being admirably vocal on a serious issue to mindlessly cheerleading that very thing she opposed is just sad.