Whats an opinion of yours that changed after age 30?

An example for me is my view on weddings. I used to just think of them as a big waste of money. Having aged and sadly lost some friends and relatives, I realized they are now often the only happy occasions everyone makes the effort to get together in one place.

Disclaimer: not intending to make this post about weddings, thats just my example because I needed a body in the post.