Has no one noticed that this app in question is still on the App Store? First result on google when you search for "Apple Watch keyboards". This makes me even more suspicious of the guy creating all this outrage. It's also not very well reviewed.
"A separate version for the Apple Watch would remain [in the App Store], but then Apple pulled that one as well, telling Eleftheriou that keyboards aren’t allowed on the Apple Watch."
https://arstechnica.com/tech-policy/2021/08/iphone-keyboard-...