It's primarily just a statement of widely agreed principles everyone has always claimed to follow, even when UNIX was new, and others arguably followed them with more success e.g.
> The Unix philosophy emphasizes building simple, compact, clear, modular, and extensible code that can be easily maintained and repurposed by developers other than its creators
Nobody says "we want to build complicated, sprawling, unclear, unmodular and rigid code", so this isn't a statement that sets UNIX apart from any other design. And if we look at the competing space of non-UNIX platforms, we see that others arguably had more success implementing these principles in practice. Microsoft did COM, which is a much more aggressive approach to modularity and composable componentization than UNIX. Apple/NeXT did Objective-C and XPC, which is somewhat similar. Java did portable, documented libraries with extensibility points better than almost any other platform.
Many of the most famous principles written down in 1978 didn't work and UNIX practitioners now do the exact opposite, like:
• "Make each program do one thing well. To do a new job, build afresh rather than complicate old programs by adding new features" yet the --help for GNU grep is 74 lines long and documents 49 different flags.
• "Don't hesitate to throw away the clumsy parts and rebuild them." yet the last time a clumsy part of UNIX was thrown away and rebuilt was systemd, yielding outrage from people claiming to defend the UNIX philosophy.
About the only part of the UNIX philosophy that's actually unique and influential is "Write programs to handle text streams, because that is a universal interface". Yet even this principle is a shadow of its former self. Data is exchanged as JSON but immediately converted to/from objects, not processed as text in and of itself. Google, one of the world's most successful tech companies, bases its entire infrastructure around programs exchanging and storing binary protocol buffers. HTTP abandoned text streams in favor of binary.
Overall the UNIX philosophy has little to stand apart other than a principled rejection of typed interfaces between programs, an idea that has few defenders today.
> The Unix philosophy emphasizes building simple, compact, clear, modular, and extensible code that can be easily maintained and repurposed by developers other than its creators
Nobody says "we want to build complicated, sprawling, unclear, unmodular and rigid code", so this isn't a statement that sets UNIX apart from any other design. And if we look at the competing space of non-UNIX platforms, we see that others arguably had more success implementing these principles in practice. Microsoft did COM, which is a much more aggressive approach to modularity and composable componentization than UNIX. Apple/NeXT did Objective-C and XPC, which is somewhat similar. Java did portable, documented libraries with extensibility points better than almost any other platform.
Many of the most famous principles written down in 1978 didn't work and UNIX practitioners now do the exact opposite, like:
• "Make each program do one thing well. To do a new job, build afresh rather than complicate old programs by adding new features" yet the --help for GNU grep is 74 lines long and documents 49 different flags.
• "Don't hesitate to throw away the clumsy parts and rebuild them." yet the last time a clumsy part of UNIX was thrown away and rebuilt was systemd, yielding outrage from people claiming to defend the UNIX philosophy.
About the only part of the UNIX philosophy that's actually unique and influential is "Write programs to handle text streams, because that is a universal interface". Yet even this principle is a shadow of its former self. Data is exchanged as JSON but immediately converted to/from objects, not processed as text in and of itself. Google, one of the world's most successful tech companies, bases its entire infrastructure around programs exchanging and storing binary protocol buffers. HTTP abandoned text streams in favor of binary.
Overall the UNIX philosophy has little to stand apart other than a principled rejection of typed interfaces between programs, an idea that has few defenders today.