That may all be true, but Sid did say repeatedly over the years that Bernie gave him whatever he wanted when it came to safety. So he played a key role. I just think that his intentions were not as noble as some might make it seem.
Bernie adopted safety issues because he knew that, having turned F1 into a show, bad publicity would affect the business. He didn't want pictures of crashed cars and dead bodies to be on the front page of newspapers the day after a race; that would be bad for the image of F1 as a respectable sport.
+1 Ayrton Senna was also a voice of safety. Here is a clip at the 91 German GP. https://www.youtube.com/watch?v=1jxSjt3wU3s
