For the life of me though I don't see what intelligence would have to gain to just make up false statements. It is not as though anybody wants to go to war with Russia who has nuclear weapons. At the end of the day the only thing done will be enhanced cyberwar tools of some sort which is a good thing IMO.
I don't believe the intelligence agencies made up false statements about Russian cyber-mischief, but there are plenty of reasons why they might, and the first and foremost is continued power.
If any group would know that the Trump team intends to shake up these agencies, it would be the CIA and NSA. I suspect that they guessed correctly that Trump would react as he did, but even if he hadn't they have set the stage for others to accuse shake-up efforts on political pay back that threatens national security. Thus the leaked report to the Washington Post which highlighted the assessment that Putin wanted Trump to win with following weeks in which no evidence was set forth.
I could, of course, be wrong about this, but if I am it's not because of the inherent honesty and integrity of our intelligence agencies.
(I should point out that I tend to exclude the FBI from membership in the Intelligence Community, and find their confirmation of the evidence persuasive if only because they are not inclined to readily support the CIA on anything. Generally speaking though, the Left now considers the FBI suspect in terms of politicization)
If the FBI Director was able to engineer a scheme to hurt Clinton's chance of winning, then certainly the CIA is able to engage in politics.
This is what these people do on a daily basis. Generally speaking they do it for the right reason which is to say to advance the interests of the US, but this doesn't preclude them from reasoning that it is in the best interests of America if their agencies were not reorganized and various leaders removed. They might even be right about that but it wouldn't be an excuse for them to become involved in domestic politics.
If there was a scheme hidden here, as I believe there was, it doesn't mean the basic finding is false or that no one should care about it. We should care though about these agencies involving themselves in domestic politics. There's no solid evidence that they were in this case, but that's not a reason to consider if they were and look for the evidence.
It doesn't seem like the scheme is going to work though. There will enough reasoned support for shaking things up and it will happen. There will be an uproar from Democrats, but the American people who voted for Trump or who are amenable to the idea of "draining the swamp" are not going to suddenly believe that waste and corruption doesn't reside within the Intelligence Community.
It has been and will continue to be amusing to watch liberals vociferously defend the CIA.