I think Barr should be commended for his restraint here. If he was really looking to send a message to President Trump, he could have just said: "I wish the President would just get off everyone's ass about this case. He can pardon Roger Stone tomorrow, and within 30 minutes I would sign all the paperwork to shut his case down. But for some reason Mr. Trump just wants to complain about other people instead of doing sh!t himself to fix the problems he seems to be having."
I'm sure that the President's legal advisors are giving him far better advice than anyone here on FR could offer. It's possible they're telling him it would be better to wait until Stone's trial is over, or after his reelection before he contemplates any pardon...especially in light of what this country has gone through with the Mueller investigation, and impeachment. Democrats are still in power in the House, and are looking for anything to investigate. Now they're looking into how much the Secret Service pays for staying at Trump resorts. They failed in their emoluments case, and are now looking elsewhere.
None of us know whether Barr went to President Trump first before he went whining to the liberal media. If he didn't, then why respect a person who does that?