Pros
The company may look attractive from the outside, and some teams still have talented individual contributors who try to do good work. There may also be opportunities to learn how organizational dysfunction affects employee motivation, trust, and retention.
Cons
In my experience, the culture was unhealthy and demotivating. After the merger, the company changed noticeably in a negative direction, with a decline in communication, trust, and employee experience. Feedback from employees often did not seem to lead to meaningful action or even proper acknowledgment. I would strongly recommend candidates do careful due diligence before applying or accepting an offer. In particular, try to speak with ordinary current or former employees — not only recruiters, hiring managers, or senior leadership — to understand what the day-to-day work environment is actually like.