Auto-Lock when you close a case

I have been told by Torro (leather cases) that the sleep/wake up function has been removed from iPhone 12 onwards.

I am so used to hearing the satisfying click when I closed my case on my iPhone XS that I was surprised that it did not work with my new iPhone 13 Pro.

Does anybody know why it was removed? It means I may have to change the auto-lock to 30 seconds to save battery life.