How do I turn off drawing mode in iOS 10's Messages?

I want to turn off the little squiggle in the bottom right corner of the Messages keyboard (the one that activates drawing mode). How can I do this? Is there a setting?

(I know the keyboard in the bottom right screen turns off drawing in landscape mode, but I want to permanently disable the feature.)

You can just delete the default Apple keyboard in the settings in favor of a different one. For example, you could download Google's keyboard Gboard, then go into the Keyboard settings, and delete the only labeled "English".

Hey presto, now you only have the Google keyboard, and it won't bring up the drawing mode whatsoever.

To Turn off handwriting in landscape mode go turn your phone to the side to activate it. Then tap on the keyboard in the bottom right. This should keep the iPhone to a keyboard when you go to landscape.

Unfortunately you can't on Apple's keyboard, there's no setting to turn it off.

Apple decided to include some additional features to the keyboard for the larger devices.

You can, however, send Apple a feedback. Sometimes they change some introduced features or add an option to disable certain behaviors.