The first time I remember fans convincing a TV network to change their minds about a series was the original Star Trek. NBC was ready to cancel the show after two seasons. A letter-writing campaign led to a third season.
This kind of resurrection is accomplished in different manners in the Internet Age. Fans have easier and more direct contact with networks and show producers. There are also many more outlets for series to continue. This isn't new ... there were shows when I was growing up that switched from one of the three networks to another, and more recently, Buffy the Vampire Slayer changed networks late in its run. Now, an energetic fan base can sometimes convince a streamer like Netflix to pick up a show that has been cancelled elsewhere.
Ownership of the "meaning" of a work of art is complicated, but some of us believe that once a work leaves the artist's hands, the meaning belongs as much to the audience as to the artist. Authorial intent is important, but it isn't a "case closed" situation. Artists can be surprised by how their work is interpreted, they can argue that their intent was not in line with those interpretations, but each of us, as individuals, create meaning out of the original work. If 10,000 people read a novel, there will be 10,000 interpretations of that novel.
All of this brings me to The 100. A television series based on a popular series of young adult novels, The 100 has never been the biggest hit ... ratings have gradually dropped over the course of seven seasons. On the other hand, it has lasted seven seasons, so the CW must be happy enough. My sense is that The 100 is a fairly standard cult series. Buffy the Vampire Slayer never had great ratings, but it was always turning up on magazine covers, and if you didn't have access to ratings data, you'd think Buffy was a massive hit. Which it was, in its way ... witness the college courses taught about the show (I taught one myself). Again, this is just my own, uninformed, observation, but I feel like The 100 has never gotten attention beyond its fan base. Even people who didn't watch Buffy knew it existed. I don't know if the same is true about The 100.
But that fan base is intense, and their sense of ownership is interesting. If each of us has our own interpretation of a work, we don't necessarily think that we should climb in a time machine and go back to tell Melville how to fix Moby Dick. Fandom today can take surprising forms, though. The question isn't "What does The 100 mean?" Rather, it is the contemporary equivalent of giving Melville advice.
Fans of The 100 have always made their preferences clear, and thanks to social media, they can make their preferences known to the people who create the show. They like this character or that plot device, they like this couple to pair up and find another couple to be uninteresting. There is nothing new about this, beyond the access we have to the creators.
In the third season, though, events within the show caused an uproar. Lexa was a popular character, a commander of clans who was also gay. Over time, a relationship between Lexa and the female lead, Clarke Griffin (Eliza Taylor), grew, slowly, gradually, into an actual romance. Shippers gave the name "Clexa" to the pairing. Alycia Debnam-Carey, the actress who played Lexa, got a job on Fear the Walking Dead, part of a franchise that is much more popular than The 100. The logistics of her being on two shows became too complicated, and so Lexa was written out of The 100. In itself, this would disappoint Clexa shippers, but the way she was written out was a disaster. After Clarke and Lexa finally seal their bond by having sex, Lexa is accidentally killed, in a too-perfect example of "bury your gays". There was an immediate uproar, and many fans announced that they would no longer watch the show. In the final episode of the season, Lexa made a brief, triumphant return in one of the most emotionally satisfying scenes in the entire series, but for many, the damage was done.
Up to this point, part of the fandom, upset at how the series was progressing, turned their backs on it while offering pointed critiques of how Clexa was ruined. Their points were well-taken.
After that, though, things seemed to change, at least from my perspective. Clexa shippers who stuck around never quit wishing things had been different (I'm one of them). Meanwhile, over the course of the seven seasons, the relationship between Clarke and male lead Bellamy (played by Bob Morley) grew in ways that worked in a narrative and character sense. They were the two leaders who people looked up to ... being The 100, they screwed up as often as they did good, but they went from being antagonists early on to being a strong partnership. For some of us, that partnership was improved by the absence of a romantic angle. Yes, a woman and a man could bond and work together without "falling in love".
But for some fans, the absence of romance was a crucial flaw. These "Bellarke" shippers thought it obvious that the two did indeed fall in love. (It may have mattered that in the books, the two do fall in love.) When, in real life, Eliza Taylor and Bob Morley married, this became evidence that Bellarke was real. But on the series, Clarke and Bellamy remained strong partners, but platonic.
And here is where things get bizarre. When Lexa died, enraged fans let the creators of the show know their feelings. But Bellarke is ongoing. If Clexa shippers decided to quit watching, Bellarke shippers are still there. But they, too, are enraged, and every episode that the two don't consummate their relationship only ups the rage factor.
So the shippers let the creators know what they think, but it's not a case of "we're going to quit watching". Instead, it's a constant message that "you better make Bellarke happen" or "you idiots don't know what we want" or "you know what we want but won't give it to us". This isn't an attempt to revive a cancelled show, as happened with Star Trek. This isn't an after-the-fact critique of the death of Lexa. This is an attempt to force a story line that the shippers think is correct.
There was a time when people wrote "slash fiction". Fans would write entire novels about the love relationship between Kirk and Spock on Star Trek, often in explicit detail. That's not what is happening with The 100 and Bellarke shippers. They want the people running the series to write their desired relationship into the actual show. And they are very demonstrative.
Meanwhile, the Clexa fans who stuck around are still out there, hoping for one last appearance of Lexa. Clexa shippers and Bellarke shippers don't get along ... it can get brutal. Both groups are insisting that their interpretation of the meaning of the show is correct, and denying any contrasting interpretation.