I'll have to rewatch the episode. I think we had a couple glances from Jim at Michael's antics, but not much. Mostly, I remember him consoling Michael about his breakup with Carol. I don't disagree about the show's style of storytelling, but they could be on the nose when they wanted to - the characters were very fallible, had tempers, and did confront each other on occasion. Doing so here could have run the risk of being preachy, but there were options on the table.
I could definitely be wrong about how this particular episode handled Michael's more insensitive antics. Maybe there was a more of that subtle storytelling than I remember. But if it's just a couple camera glances from Jim, and then he explains what a "rebound" is to Michael with no mention of it, that could be taken a certain way, although it probably is in line for Jim's character, who was more go with the flow, especially early.