Onscreen keyboard is the only option for text entry on the ATV4. Only Apple knows if/when they plan to update the remote app but as this is a user forum no one can answer with any certainty...
Step 1: On your Apple TV, go to Settings → Accounts → iTunes and App Store → Password Settings.
Step 2: In the section labeled Purchases And In-App Purchases choose the Require Password option.
Step 3: Now set your preferred level of protection to Never. You can also choose to be reminded to Always enter password for purchases or After 15 Minutes.
Step 4: Also select Require Password under the Free Downloads section and choose Never to turn off password prompts when downloading free apps from the App Store.
Tip: If you set Require Password to Never in step 3, there won’t be an option to turn this setting on.