I can confirm this is still valid.
I bought a 9.7 smart keyboard second hand mid way this year which was working perfectly. Most recently, I had the 'accesory not supported' toggle increase in frequency which led up to the eventually non-detection of the keyboard and sticking of keys. I went to the apple store this week in Melbourne where I live and was able to get a brand new replacement model free of charge without a receipt.
Honestly, I didn't know when the original buyer had purchased the thing so I was betting on the fact that it would still be in warranty and made it seem like I had purchased it but forgot when I did and lost the receipt. All that was needed as the serial number which was hard to read, but after figuring it out, finding out that it was indeed still in warranty, and demonstrating that the keyboard was non functional by testing it on other ipads at the store, they agreed to give me a replacement.