Several reasons:

• Compilers strip all the bullshit from the code. Most software projects have shitty code structure and navigating them without prior exposure is a bloody nightmare. Everything gets a lot easier in binary.
• Compiler optimisations flatten the code into an easier to understand structure. You don’t have to just around function definitions in multiple files when the compiler inlined them all for you to see on one screen.
• Assembly debuggers usually have a lot more features than source code based ones: trapping OS calls, scripting, etc. They make life so much easier.

Most software developers have no fucking clue how computers work, it’s all magic to them. People joke about “vibe coding with AI” these days, but let’s be real, 99% of software developers are vibe coders, but with Google instead of AI. Of course these people will never understand a bit of assembly, they can’t even fucking grasp the basics of higher level languages!

There’s nothing hard about binaries, code is code.