The author’s intent in How to Train Your Dragon was for the Goal to not succeed. This isn’t to say that the Authors weren’t rooting for Hiccup, but they were also rooting for the efforts of the elders to fail. A clear change in how things are done. There is a clear bittersweet feeling to the ending that feels more Personal Failure than Personal Tragedy.
As far as Die Hard goes, it’s clear that it is a Triumph with everything from Bruce reuniting with his wife to happy Christmas music playing in the background. Bruce is therefore Protagonist in the eyes of the author.
(Sorry, I know you asked Chris, but I couldn’t resist)