This is kind of a cheap shot at people who just wanted built-in syslog support. There are plenty of reasons someone might not be able to patch or upgrade a binary, and using a fifo is a pretty bad kludge considering the whole thing can hang if they're started/stopped in the wrong order (meaning your startup scripts now have to be rewritten). Building in syslog support means just getting the damn thing working without special hacks and kludges.
But to answer OP's question, syslog is better than just appending to a file because syslog does a lot of things for you, like filtering your logs in real time and splitting them into new files, logging remotely to industry-standard aggregation devices, access control, (somewhat) standardized formatting, log rolling, etc.
But to answer OP's question, syslog is better than just appending to a file because syslog does a lot of things for you, like filtering your logs in real time and splitting them into new files, logging remotely to industry-standard aggregation devices, access control, (somewhat) standardized formatting, log rolling, etc.