It looks like "nerd" or as other Reddit said "help data screen" due to bad startup.
I would try... Rebooting the TV (or cold restart by unplugging TV, wait 15 secs, plug back in).
Or maybe look in your menus first for a setting turned on like "nerd stats" or "show technical details".
I don't have my Android TV setup right now to test for you. My guess is it is a stats screen.
Also check for any debugging options that are enabled, most likely within developer options.
Click the “i” button on your tv remote
You probably went to the secret menu yes? Because TV has restarted in some diag mode.