So yes the Motorola synthetic back is definitely more durable than glass.
I was thinking more in terms of durability relating to general wear and age rather than short-term drops, scratches, etc. I’ve seen some images of people claiming their Motorola back wore out within months (could be a problem on their end, mine is fine after a year) and we all remember those older plastic devices with the soft touch finish that “melts” after a few years.
This is not a leak, it is just a prediction from some random based on their weird analysis of the market. Pure clickbait.