I don't know the counts of Unix and Linux servers. I do know that my heart sinks whenever I look under the hood in Linux. It is has been so overfed by loving hands. Over 240 system calls! Gigabytes of source! A C compiler with a 250-page user manual (not counting the language definition)! A simple page turner, 'less,' has over 40 options and 60 commands! It's proof that open-source can breed monsters just like the commercial pros. Miraculously, though, this monster works.

Doug McIlroy (2013). In their own words: Unix pioneers remember the good times