Are carbon fiber speaker cabinets inherently better than wood or metal ones

It's lightweight and rigid and, more than anything else, provides the perception of modernity to the consumer.

Wood is so 19th century!

Call me old fashioned, but give me a beautiful cabinet make of burled walnut or birds eye maple any day. 

It takes a lot of  time and specialized labor to get satisfactory results with carbon fiber compared to applying wood veneer over a MDF box.  

The sound is faster, coming out of a corner when it is made from carbon fiber

I’m guess here. The speaker designer is making compromises throughout the design process and view the various designs as a system. 
 

I imagine Sonus faber believes using natural materials for the cabinet is a critical aspect of their design. An I think Focal, Wilson and others would make the same comment. Not sure what Magnapan’s perspective would be though!

Ultimately it there’s excellent options and beauty is in the ear of the beholder