Hi TheRock6119,
Thank you for participating in the Apple Support Communities. We understand you'd like to be able to automatically delete videos associated with Messages. The only methods for deleting videos in Messages can be found in this article: Delete or hide photos and videos on iPhone.
"Delete or hide multiple photos and videos
While viewing photos in an album or in the Days or All Photos view in your library, do either of the following:
- Delete: Tap Select, tap or drag your finger on the screen to select the items you want to delete, then tap
. - Hide: Tap Select, tap or drag your finger on the screen to select the items you want to hide, tap
, then tap Hide."
If you don't need the Messages in their entirety, you could have all your Messages automatically delete after 30 days or 1 year. Go to Settings > Messages > Keep Messages.
If automatically deleting videos is a feature you'd like to see added in the future, you can leave Apple feedback here: Product Feedback - Apple.
We hope this helps.
Take care.