An ominous but important appraisal of our current situation.  You are not the first to voice these concerns and whilst the question always reverberates around the community, bringing to the table so many different potential solutions... nothing seems to change.  And your description of how these questions were met seems to tell us why.

One thing I will say is that thankfully there are many now who delegate SP.  And sometimes it is delegated specifically to those who challenge the status quo.  So while one 'big player' may not agree with the link between vaccines and autism, another will.  

But in the end the real power is still in the hands of those few big players.