Your grammar is down. The comma after the replicated is due to the fact the last phrase is an independent clause.<quoted text>
If you're going to critique the spelling and grammar of others, please ensure thine own house is in order beforehand.
In your statement "That kind of consistency is not easily replicated, and neither is someone's syntax", a comma should not be used after the word "replicated" because it is immediately followed by the word "and" which is a conjunction. The exception would be if you were listing multiple words in sequence (e.g. "I will bring balls, bats, and gloves to the game").
Have a happy topix day!
Serial commas as in your example of bringing balls, bats, and gloves are a matter of style, not grammar. You may refer to the Chicago Style of Manual, 15th ed., 2011, reference here:
Serial commas are more typically found in technical materials, not in conversational narratives however, such as in novels or letters.
You've now gotten a lesson from the queen, GPA 3.87, Capital University, majors in English, comm, marketing, and have been working as a tech writer/editor for nearly 25 years. Have experience with a wide variety of style manuals from CMOS to AP to MLA. You're welcome.