Well, you're literally writing step-by-step instructions that a computer will faithfully perform without deviation. Once you understand how a computer works and how to talk to it, it should be as easy as having a conversation.
I don't think this is easy, but when you've been doing it for years and years, it feels that way.
Computers don't even operate solely step by step anymore. They often operate asynchronously, through interrupts, or compute things in parallel across multiple threads.
Maybe if you're programming something simple, it will be "step by step". But most programs are not this simple.
I don't think this is easy, but when you've been doing it for years and years, it feels that way.