I think you're right in that these days the audience might have more influence on the creators than they have in the past, and the example you give of the telenovela is certainly interesting!
From what I understand though, SessKag seems to be mainly popular
outside of Japan. Please correct me anyone if I'm wrong! But at least I've seen very little SessKag fan art or doujinshi made by Japanese artists.
Anyway, because the main audience Takahashi and her editors at
Shogakukan are concerned about is the Japanese audience, I highly doubt there would be any pressure to make SessKag canon even if the show was taking place in a more social media dominant era than it originally was.
I think it's a fine line to walk though. Certainly you have to have respect for your audience, but also you might have a vision of your story you are unwilling to compromise on, even if it might alienate some of your readers.
Honestly, I just don't personally understand the mindset either of going to the creator and telling them what I would like to see happen?
And in any case I think fandom in recent years has become overly concerned about canon. What does it matter if your ship is canon or not? I mean that is what fandom and fanworks are for!
If I got all that I wanted from the canon itself, there'd be no need for me to go look for fan art or fics, let alone write ones myself!