Amazon Shifts Its Policy - Because of Me?

Amazon is a very large global business. Everyone knows that, particularly if you're in the publishing business. But as I explained a few months back, I was attacked by users of an Amazon sci-fi forum and made the mistake of arguing with them. They then started posting negative stuff on one of my book pages, claiming my work was no good, despite the fact they'd never bought or read it. I wrote a long letter of complaint to Amazon's legal department. They consequently removed the comments. Obviously I was pleased about that. But then I discovered recently that they have now changed their policy, world-wide, so that people who have not bought the book they're commenting on, cannot post comments, reviews and so on, unless that book is listed on the books they've purchased through their account. In my letter I suggested that they should do this. And they have done it. Whether it was because of my complaint to them, who knows? But at least it stops those who wish to do damage to others from posting unpleasant stuff on your book page!