I don't really have a dog in this hunt since the Rams aren't in the Super Bowl but the only undisputed facts so far are that the balls were under specified pressure
when tested with a gauge at half time.
It has still not been established that they were tested with a gauge prior to the game. The NFL statement says: "Prior to the game, the game officials inspect the footballs to be used by each team and confirm that this standard is satisfied, which was done before last Sunday’s game." Notice it does not say how the inspection was conducted (i.e.: with an air pressure gauge). So at this point, we are expected to assume the pressure was actually tested with a gauge. Proper wording can be very important since certain words may imply things which are not absolute facts. Businesses use these tactics all the time when making press releases. I would expect nothing less from the NFL and neither should anyone else. In this case, the choice of words may mean nothing or they may be the difference in whether the refs actually tested the air pressure with a gauge or just gave the balls a squeeze. At this point, we don't know for certain which is the truth (and given the way other investigations have been conducted, we may never know either).
Second, I have personally experienced instances where two different tire gauges gave me very different readings on the same tire, so it is possible the Patriots believed they gave the NFL properly inflated balls, the refs squeezed them and thought they were ok, passed them before the game and then found at half time they were not.
Finally, Aaron Rodgers has said the Packers try to get over-inflated balls past the refs (over-inflated balls would also be a violation/cheating) and lamented the many times it was unsuccessful. Since it was clear from his statements that this has been done multiple times, the question becomes why try if you were caught every time? The fact they have tried repeatedly suggests they have been successful at some point.
Now, I am not saying any of this is fact and it may well turn out the Patriots broke the rules. If that is what the investigation finds, so be it. Assess the prescribed penalty and move on. Couldn't care less. But I am unwilling to say they cheated as if it is a certainty when the actual facts (not supposed leaks) do not yet support that presumption.