Good point--it probably wasn't cancelled JUST because its existence got leaked. Though if it was, I still support that. Trust is sacred. We can't have anything good in this world if people think it's okay to break a promise of trust.
It's totally possible to make medieval live action without blood/gore. In fact, throwing off that trend is the main reason why Game of Thrones took off: It was shocking. It pushed the boundaries of what we thought was possible to show in media. It's also part of why Game of Thrones's popularity took a big dive after the show ended, rather than becoming a cultural mainstay. You can always get easy attention for pushing boundaries, but after that shock value is normalized, there's little reason left for anyone to pay attention. The first silent film to be banned for pornography was just a woman in a big frilly dress twirling around.
I like to compare Game of Thrones to The Legend of Korra. They both have dark and gruesome deaths, but the directors make a very conscious choice in whether we're shown the violence (for thrill) or the faces of those who witness it (for sympathy). What does the audience literally see? There are lots of other little things that are purely aesthetic, like do we have the character stab their opponent in the face and gouge his organs out with blood flying everywhere, or does the character slice their opponent at chest-level, showing us simply a tear in his armor as he falls to the ground? No matter what the subject material, it's the directors who decide what kinds of visuals, emotions, and attitudes the audience is exposed to.