Apple Watch Series 6 kills ceramic Apple Watch Edition material... again
The Apple Watch Series 6 has debuted at Apple's "Time Flies" event, along with new features, and case finishes. However, one on-again, off-again case material was absent.

Apple has yet again decided to remove the Apple Watch ceramic case option. Ceramic originally debuted with the Apple Watch Series 3, but not included in the Apple Watch Series 4 lineup in 2018.
It was brought back for the Apple Watch Series 5, which raised the price to $1,299 at the cheapest, with a maximum of $1,749. Apple has yet again decided against adding ceramic to the newest Apple Watch lineup.

Apple Watch Series 6 shown in the Apple Watch Studio
Instead of ceramic, the Apple Watch Series 6 is available in aluminum, stainless steel, and titanium. The aluminum version comes in two new colors -- blue and (PRODUCT)RED.

Apple has yet again decided to remove the Apple Watch ceramic case option. Ceramic originally debuted with the Apple Watch Series 3, but not included in the Apple Watch Series 4 lineup in 2018.
It was brought back for the Apple Watch Series 5, which raised the price to $1,299 at the cheapest, with a maximum of $1,749. Apple has yet again decided against adding ceramic to the newest Apple Watch lineup.

Apple Watch Series 6 shown in the Apple Watch Studio
Instead of ceramic, the Apple Watch Series 6 is available in aluminum, stainless steel, and titanium. The aluminum version comes in two new colors -- blue and (PRODUCT)RED.
Comments
In fact, the Series 2 was the first Apple Watch with a ceramic case.
My loop (no coating) has almost never had a chance to touch the glass; I either use the watch, or I charge it.
However, I think we would have heard about it if your problem was a common one. Did you do anything potentially different with yours? Maybe keeping it in your pocket a lot, while moving around?