Maxperson
Morkus from Orkus
Well, Crawford’s ruling isn’t that the feat specifies a timing for the bonus action, per se. It’s that it sets up a precondition that needs to be satisfied before the bonus action can be used. Where I disagree with Crawford is that a rules precondition necessarily operates as a precondition in the fiction. The wording of the feat suggests to me that as long as you take the Attack action at some point during your turn that you can also take the bonus action shove on the same turn, so taking the Attack action is a precondition at the table but doesn't need to come before the bonus action in the fiction. The fact that Crawford originally ruled this and other bonus actions as working this way also strongly suggests that this was the intended interpretation when it was written.
The wording of the feat does not in any way suggest that you can take the bonus action prior to the action. It explicitly states that IF you take, THEN you shove. Prior to actually taking the action, you have not taken the action, so there is no trigger for Shield Master to work off of.
The feat doesn't require you to shove a creature you've already attacked. You can use your Attack action on one or more creatures and use your bonus action shove on an entirely different creature. I don't believe there's any reason to think there's an intended narrative of setting up an opponent to be shoved.
This is a good point, and just makes game balance more likely to be the reason Shield Master works differently.
If that's true, then why didn't Jeremy Crawford come out and say so? His stated reason for changing his mind on bonus actions is that it's a more literal interpretation of the RAW. I don't see any reason to question his honesty in this regard.
I have no idea why he hasn't come out and said it. He's also correct about it being a more literal interpretation of RAW, but if that's all it was, he would have said something like he did with Disintegrate and Wild Shape. In that ruling he let us know RAI prior to saying that the druid by RAW does in fact dust as soon as the wild shape form hits 0 hit points.