It hasn’t been disabled intentionally as you suggest.
That is a known bug that is scheduled to be fixed in the next app release which is currently in the final rounds of RC Beta Testing which was released to the Beta Testers on Wednesday. If you would like to get the Beta RC App, you can sign up to be a Beta Tester.
Wyze acknowledged this bug and updated users as to the fix here:
If it had been disabled, you wouldn’t be able to access the playback from Live View, which you can, or be able to use the playback icon when you tilt your phone to watch the event in landscape, which you can.
This bug only affected the iOS app playback button in portrait mode.