I really don't think that's it. James Caldwell of the Torch thinks it's a reaction to the awful rating on Monday's Raw. If that's the case it's kind of odd that you'd put the strap on the guy who main evented* that episode.
If anything I tend to think it's a way to a) get us to the Shield three-way match people have been clamoring for and b) a full-blown heel turn for Roman Reigns.
*To be clear, I don't pin the rating on Ambrose because that Raw looked like an episode that the real main event was on earlier in the show anyhow, but it does make you look at that claim like O_o.