We'll never know, but he was the first choice for both roles. Peter Jackson wanted him so badly he was offered $30 million salary plus 15% of box office gross. That decision cost Connery an estimated $450 million. His stated reason for turning down the role was he didn't understand the story. He read the books, read the script, and didn't understand the story. Who the fuck doesn't understand The Lord of the Rings?
Oh I see. Actually, this makes a lot of sense. Wow. So he made a choice beyond money? Obviously, he understood the position of the role and the expectations and the crazy fandom. Guys, it is Gandalf. Gandalf. It looks like he realised he wouldn't get into the story and the role and refused. RESPECT. I just checked, his net worth was 350 million at the time of his death. Why would he need more, it wouldn't make any better impact in his life.
Christopher Tolkien has recieved death threats over the movies and had to declare he had nothing to do with it if memory serves right.
Masses of people do not understand anything about The Lord of the Rings. Because it is a culture, more than a book or a movie trilogy. They just like the action and visual effects which is important as the movie is a milestone but they are mostly too young to get that.