Except it isn't. That's an amusing conspiracy theory to have, but it doesn't make a lick of sense, because they can target whatever frame rate they want to. They're not beholden to one or the other, but the fact that they decided to target 30fps over 60fps compounds their points, and they've explained why they went that direction several times already.
Hell, it's abundantly clear even when playing their recent single player campaigns. The level of fidelity, the size of the arenas and levels, the quality of animations and physics, the lighting, geometric and foliage density etc, it's just far removed from what we see in 60fps PS4 console games, or even compared to their 60fps multiplayer modes.