SCRUM masters are often submerged in the belief that the agile way of software development is the only way and a silver bullet. They are recognizable by sharing cartoons trying to make people thinking anything else look like fools. Well, SCRUM is no silver bullet and fails as other methodologies do. Sharing these cartoons show who the fools are.
The type of stakeholders and tasks in a project will influence if a combination of methodologies can be a better approach in the project management than a single methodology. It is possible to create your own project management process.
Here a short video with initial thoughts on creating your own project management process. The creators of the video give courses in project management, and have clients like Amazon, Netflix, Uber and Starbucks. They also offer a tool for project management, shown in the last 1/3 of the video, where they show how a mixed management process can be implemented in their tool. The first 2/3 of the video is the most interesting though.