Agree with the majority of posts here that you did the right thing, before you beat yourself up too much , remember this
1) You did not agree with him, but you calmly tried to offer the alternative argument.
2) we all have friends that have polar opposite beliefs, be it political, religious, social - but unless they are total racists and/or bigots, we still are friends with them
3) Having such a discussion with a baby boomer vs a millennial or a gen-x poses a ton of addition challenges, from years of upbringing and applied social norms.
4) I am sure that opening yourself out to him would have destroyed your friendship
