Except the cases the Post commented on are mostly tongue-in-cheek. Yeah, there are benefits of getting into search terms, but at least it's not word soup. I have two long subtitles, both are tongue in cheek and not just a combination of keywords.There are some long subtitles I love when I read them because they make me snort out a laugh. And then there are those that cause me to roll my eyes and snort in derision.
However short of limiting the characters to X, there will always be people who take advantage of the situation. Although, Amazon is also a blame here. They came down on subtitles a while ago. You couldn't use a subtitle that was also a category. You can't subtitle your book, A Romance. Some of those multi-word subtitles is a way to get around that Amazon restriction, and while annoying it's at least understandable.