Many people who choose to make alliances were previous high-up government officials in larger, older alliances. The main reason they choose to create a new alliance is because they wanted change in their old alliance (most of the time, at least that I have seen in my CN experience is that one or two senior alliance members do feel that the alliance belongs solely for them. This creates a hierarchy that is difficult to break.). These people who do create alliances have tried to change the former system but ultimately failed due to old procedures in the alliance or senior members who are not willing to try the new change. If their alliance was so great, they wouldn't have even thought about leaving (especially if they enjoyed the government position they probably held).
With that, I do agree that there are going to be a lot of mergers in the next few weeks as the end of summer nears. A new alliance is a lot of work and is definitely not a one man job. I've seen new alliances either thrive shortly after their DoE or fail and result in a merger due to lack of activity. Only time will tell which will happen, but I have a feeling CN will return to normal after this war dies down and school resumes in the fall.