If the argument about the force out being too subjective and therefore the rule should be changed...
So should many of the other rules that exist. Pass interference for one.
Granted, we're talking about a complete/incomplete pass vs a penalty/no penalty. But the point is the same.
Officials have to make subjective calls all the time.
I don't dispute that officials make subjective calls, but I am suggesting that the force out rule adds an additional level of subjectivity to the official's decision, such that asking him to make this call is unreasonable.
With pass interference or holding, the official sees contact. He then mentally compares that contact to how pass interference or holding are defined by rule, and he judges whether what he saw meets the definition of the illegal behavior. He's make a judgement on whether something he saw (i.e. something that really happened) is a penalty or not a penatly.
With the force out rule, you are asking the official to make a guess as to whether something that didn't happen might have happened absent a "push". Among the things that have to be taken into account in making this call, is the ability of the receiver. On a sideline play, doesn't the likelihood of the receiver to get his feet down in bounds depend on his skills and abilities? Not all receivers have equal abilities.
So for a given sideline catch situation, absent the push, if super-stud all-pro wide-out is the reciever, it might be reasonable to assume that he has the skills to get his feet down. But what if, in that same sideline catch situation, it is backup bruiser full-back getting a chance to catch his one pass of the year? He simply may not have the skills to make that reception. You are asking the official to decide whether the receiver has enough ability to get his feet down absent a push. Are officials trained as talent scouts? Do they study every reciever for each game and have them graded as to their abilities to make sideline catches?
Then there's also physics. You are asking an official to evaluate momentum, velocity vectors, aerodynamic factors, etc. Computers have a hard enough time with that, let alone a human being asked to make a split second decision on where a moving body might have ended up.
The force out rule is just a "feel-good" rule that overcomplicates the game. Time for it to go away. If there is a force rule for receivers, shouldn't there be a rule for QBs who get hit while throwing (i.e. if the QB had not gotten pushed while throwing, the pass would have been on target and completed)???