I don't see what the problem is personally. If you are in the middle of typing a message and you need to scroll to read a longer text, the keyboard disappears but the message you were typing still remains in the text box. This allows you to read the message easier (without the keyboard in your way) and also allows you to keep your message that you were typing. Taping adds ANOTHER task, where scrolling up is seamless as you would be scrolling to view the previous messages anyways.
But, you might as well add a few more



and it may get better.
Have a good day,
Adam
But, you might as well add a few more
Have a good day,
Adam