Going off memory here admittedly, but the Rams' defense did a great job of taking things away and letting that pressure wear him down. Truth is any QB can have a bad game vs a top defense, and if the Rams' defense is a top unit then that type of performance is going to be par for the course for opposing QBs for the most part.
I'm not convinced that Carr is damaged goods. He's in a new offense with a new voice in his ear facing a top defense. Or so I think right now. Let's wait and see how he does over the next few games, he's got the Broncos who are solid up next but then the Dolphins and Browns and I suspect he's going to rebound with that offense growing game to game.