There are a number of reasons why so many developers say they just use Vim when programming. Some of the most common reasons include:

• Efficiency: Vim is a very efficient text editor. It allows developers to edit code quickly and easily, without having to take their hands off the keyboard. This can be a huge advantage when working on large or complex codebases.
• Power: Vim is a very powerful text editor. It has a wide range of features that can be used to edit code more effectively. For example, Vim has features that allow developers to quickly jump around in a codebase, to search for and replace text, and to refactor code.
• Customization: Vim is a very customizable text editor. It can be customized to meet the specific needs of each developer. For example, Vim has a built-in programming language that allows developers to create their own custom commands and plugins.
• Portability: Vim is a very portable text editor. It is available on almost every platform, including Linux, macOS, and Windows. This makes it a good choice for developers who work on multiple platforms.

In addition to these reasons, many developers simply prefer the way that Vim feels. Vim is a very modal text editor, which means that it has different modes for different tasks. This can be disorienting at first, but once developers learn how to use Vim effectively, they often find that they can edit code much faster and more efficiently than with other text editors.