Your use of the word "only" is both correct and illuminating.
Mueller seemed to want to clear up any misunderstanding that he concluded that Trump committed a crime, and that the only reason he didn't indict was the rule. Mueller wanted to say that he did not reach a conclusion either way, and you certainly wouldn't indict if you hadn't concluded that Trump committed a crime. You are correct there. But Chris is too. Why did Mueller decide not to reach a conclusion? After all, isn't that what he was supposed to do? He didn't reach a conclusion because of the rule. He did, as I understand it, conclude that the individual elements of obstruction of justice had been met. He just refused to take it further, because he could not bring charges.
There really is no way to read it the way you guys are reading it. If Mueller felt like he didn't have enough evidence, he would have exonerated the President, and yet he went out of his way to clarify that he could not exonerate the president. He clearly felt that he did have enough evidence, but chose to stop short presenting a conclusion as to whether the President committed obstruction.
As for your comments about Barr telling Mueller to ignore the rule, that seems completely contradictory to his unsolicited love letter memo he wrote (for no legitimate purpose) explaining how the president couldn't be charged with obstruction of justice. Maybe Mueller felt he couldn't take a possible misreading of some conversation as a legitimate complete reversal of Barr's widely publicized memo.
I hate even talking about this stuff. I am trying to figure out who's information/belief bubble is less correct. I have to say I agree with Chris on this issue.