Neither the article nor the backing paper discussed made any such definite claim.

Many casual readers confuse statements such as

  "which *may* have had symbolic or ritual significance."

Attribution of potential cause of inferred behaviour to "ritual" is a long standing practice in archaeology; it's code for "we don't know" and covers all manner of things that may simply have developed as habit over years, may have unknown and non supernatural causes / motivations, etc.

Perhaps "symbolic significance" could simply by about signifying "I'm good at knapping cool looking material" or "I had enough resources to trade for this hard to knap tool". The symbol of status/skill, essentially. People like to show off.

It is like the go to explanation for things they don't have an answer to. What if the quartz arrow head was just a status symbol or was traded as a luxury item?