Before I begin, I want to communicate one thing: I am a Destiel shipper. I see what you see. I've seen every episode of Supernatural and I know all about the history of these two characters.
Supernatural is a show that has taken on a life of its own through the years. Currently on their twelfth season and already renewed for the thirteenth, the fans have continuously supported the show, characters, and actors. So there has to be something that keeps bringing them back week after week, right? For a lot of people, this reason is what is commonly known as "Destiel"- the relationship between Dean Winchester and Castiel.
Since Misha Collins' character of Castiel appeared in season four after rescuing Dean from hell, the "profound bond" (Castiel's own words, not mine) between the two of them hasn't gone unnoticed by fans. And, for a lot of these fans, Destiel is what keeps bringing them back week after week.
And, don't get me wrong, having this as your reason for watching the show is fine. Just don't become blind to everything else happening. This show is so much bigger than a ship. Week after week, social media is filled with people complaining about the latest episode. However, they aren't complaining about the writing or the plot or anything along those lines. Rather, they're upset and complaining about the Cas/Dean interactions. Or, more often than not, lack thereof.
Instead of recognizing the amazing acting or acknowledging what the plot of the latest episode could mean for future episodes or appreciating the characters as individuals, the Destiel relationship becomes all they look for while watching and, in turn, all that they can focus on when talking about the episode.
Even if Destiel were to become canon somewhere down the line, this relationship would never and should never be the main focus of the show. It's not what Supernatural is about. It's simply a small part of a much larger picture. The show is about family, sacrifice, bravery, and growth. Yes, Destiel could fit into some of these categories, but it doesn't define any single one of them.
If Destiel were to become a thing, that's fine. If Destiel doesn't become a thing by the end of the series, that's fine too. Because I've grown to love the show as a whole, not for one specific thing. Everything about it brings me back week after week, not the hope that Destiel will become something we all can enjoy outside of fan fiction.
So, next time you watch Supernatural, actually watch it. Appreciate it for what it has, not for what it doesn't.