Has anyone been denied access to VA healthcare based on filing complaints of malpractice, negligence, or filing a disability or FTCA claim?

I have read and heard from other veterans that the VA red flags files of those who makes complaints of malpractice or files complaints of not receiving quality care, even to the point of them being denied healthcare. Would this action be considered to be a retaliatory reaction in which legal recourse could be initiated by affected member?