I completely agree, suggesting the actual diff is the ultimate "put up or shut up". One of the most annoying review situations is when you get some vague comment that doesn't spell out what change is being asked for.
Although the best response to that sort of thing is just a quick DM - "hey, I'm not sure how to interpret this comment, wanna hop on a call for a minute and explain?"
Again - put up or shut up. Want a change? Cool, let's pair on it. I want the code to be good too. But I'm not going to just read your comment and based on the vibe I'm feeling shoot off some change, only to find out that it wasn't what you meant.
