So far, we know that Trump and Barr really, really don't want us to see what's in it.
Why that is, we can only speculate. It's a sure thing that any attempt to keep Congress in the dark will be a disaster for the Trump WH.
If that were true, Trump would exerted executive privilege, but he didn't. Your speculation is just nonsense.
Barr has no incentive to dishonest about what the report says because now that it is released, his words and the report can be viewed side by side. If he was lying, it would be made clear.
Rod Rosenstein and Mueller lawyers had a hand in the redactions and White House made no redactions at all. So, you really have no basis for your claims. It's just wishful thinking on your part.
The fact is that Trump didn't collude and didn't obstruct justice at all. None of that is true. While there may be some things that are politically embarrassing to the White House and the president, the accusations of collusion and obstruction are not simply not supported by the report.
It is important to note that since the report is viewable by everyone, it is also viewable by the entire Mueller team. So if Barr didn't put out the same report the Mueller team sent to him, they would call him out on it. But they didn't.
All redactions are according to existing law that Barr had to follow and he is willing to allow private viewing of the redacted portions by members of the Judiciary Committees.