Hello lchernabog,
Thanks for posting in the Apple Support Communities.
We understand you accidentally deleted some texts on your iPhone after updating to iOS 16 and looking to recover those, right?
If we have understood correctly, check out the steps below to see if you're able to retrieve the deleted message. If you can recover it, see if the message is still marked as spam or not. You can locate these steps and other information here: Delete and recover messages on your iPhone or iPad - Apple Support
Retrieve a deleted message or conversation
1. In Messages, tap Edit.
2. Tap Show Recently Deleted .
3. Choose the conversations with the messages you want to restore, then tap Recover.
4. Tap Recover Message or Recover [Number] Messages.
You need iOS 16, iPadOS 16.1, or later to recover deleted messages and conversations. You can only recover messages and conversations that you deleted within the last 30 to 40 days.
Let us know what you find after giving that a try.
Have a great day!