I think I know the issue. What happened when I updated is that I lost the ability for predictive text. Go to settings > keyboard and make sure predictive is on.
But this won’t completely fix your problems. In the past I’ve typed words like ugh, meh, smile, happy, etc. just to get the emoji’s to pop-up and the ability to tap to send.
Compose a message to anybody go to the emoji keyboard by tapping on emoji icon in the bottom left of the keyboard and tap out a bunch of random emoji’s. Pizza, smile, cowboy, whatever. You don’t even have to send them, delete them, then try your message again. Or try to type the word smile and see if the smile emoji’s pop up.
This worked for me.