If the E-25 wasn't already a premium vehicle and only available in the one configuration, I'd suspect that this was a play to make a version of a vehicle from the World of Tanks MOBA. I don't know about other players, but when I see tanks with guns like these, like the /L100 guns researchable for some vehicles, I tend to refer to them as 'lolcannon' for their lack of real-world utility, only the game's lack of collision modeling for cannon barrels keeping them playable on many maps.