If you objectively look at all the facts in this case, which includes Amazon's monopoly position in the eBook market, and near monopoly position in physical books, at the time all of this happened, you are left with only 2 possible explanations:
1. The lawyers at DoJ are utterly stupid and unable to see the effects this would have on the publishing industry if they prevail.
2. Someone at DoJ controlling this process is completely corrupt and either paid off by Amazon (or promised future "compensation") or they or someone close to them owns a lot of Amazon stock.
Nothing but long-term, severe consumer harm and damage to the publishing industry can come from the DoJ winning this case and handing Amazon monopoly control of the entire publishing industry. And I for one don't believe the lawyers who work there are that stupid. (Although, there were those hires by the previous administration that were based on political views and not professional qualifications.) So it's very hard not to conclude that this entire proceeding stems from some utterly corrupt person or persons at the DoJ.