In my experience, Scrum can easily become a series of little waterfalls, rather than bring a flexible and needs based approach to building complex products. This lead me to see that Scrum is not really Agile, where by “Agile” I mean . Scrum is a process and Agile is a mindset. Some teams are able to hold both ideas in their head at the same time. But in my experience across multiple large customers and projects, teams think that by doing Scrum they are being Agile, and this is not the case at all.
Scrum is no more a solution to the social and political problems of a project than is waterfall or the spiral model (which Scrum mimics IMO) or anything else. A good team will succeed regardless of the project management methodology and a bad team will most likely fail.
Scrum is not the problem nor the solution. It’s management’s job to ensure that the teams are working well, that people have room to succeed and fail, and that the project management methodology suits the needs of the project. That’s certainly where I failed my business for a few years, until I worked it out.