I decided to refresh my memory of what exactly came with the Knights Pledge and I came to the realization that the original (unfunded) Kickstarter Knights Pledge included several rewards that were not featured in the Knights Pledge located on the Pantheon website. I'd love to know if the Ogre Taurokian Warhorse is still in the works, even if it's not a pledge reward!
The devs have expressed their commitment to fulfilling all pledge rewards that were included at the time you pledged. So if anyone still has that pledge from 2014, they should still be entitled to it. (Kickstarter pledgers had an opportunity to transfer their pledges to the new website if they provided e-mail proof of their KS pledge. Hard to say how many people are still holding those pledges.) The devs occasionally remove certain perks from pledges so they don't get too out of hand. But no one would be retroactively stripped off a reward they signed up for. After the Kickstarter, the team did a big revamp of the pledge options to not have pledge rewards that could be interpreted as P2W. So in this case, it's an interesting predicament. My guess is maybe it's just a cosmetic mount that doesn't actually provide any run speed bonus? Or maybe very, very minimal?