Why is tourmaline so popular?

Hello friends. I would like to start a discussion for my own education on why tourmaline is so popular. In my experience tourmaline gemstones are often underwhelming in color and lacking optical performance compared to other stones. They are very frequently muddied in tone and lacking in brilliance and surface luster. I rarely ever see glimmers of dispersion from even well cut custom gems.

with alot of gems the rarity is what gets people i think