The best programming operating system is subjective. It depends on your preferences, and on the programming languages and tools you are using. Here are the popular options and what each one is good at.
macOS
Many programmers favour macOS, particularly those working on iOS or macOS software. It has Unix-based command-line tools, a sleek interface, and compatibility with a wide range of development tools and environments.
The iOS point is not a preference, it is a hard requirement. Xcode only runs on macOS, and building or submitting an iOS app needs it, so that decision gets made for you regardless of what you would otherwise choose.
Linux
Many developers prefer Linux because it is open source, has a robust terminal, and is highly customizable. It also offers a wide range of programming tools and environments, which makes it a popular choice for web development, cloud computing, and data analysis.
There is a practical argument underneath the philosophical one: servers and containers overwhelmingly run Linux, so developing on it means your machine resembles production. Path handling, file permissions, and case-sensitive filenames all behave the same way in both places, which removes a whole category of bug that only appears after deployment.
Windows
Windows is widely used in the enterprise world and offers tools and environments for programming in a range of languages. Visual Studio, a popular development environment, is available on Windows, and many other programming tools are designed to run on the platform.
It is also the least either-or of the three now, because WSL runs a real Linux kernel alongside Windows. That closes most of the gap for server-side work while keeping the applications that only exist on Windows, which is a reasonable position if you need both.
Ultimately the best programming OS depends on your personal preferences and the specific tasks you need to accomplish. It is worth trying a few and seeing which one works best for you. The honest summary is that all three are workable for most things, and the decision usually gets made by one hard constraint: what you have to ship, and what will only build on one of them.
