I can report that both MSConversation.sendText(_:completionHandler:) and MSConversation.insertText(_:completionHandler:) are completely broken for me since iOS17. MSMessagesAppViewController.extensionContext.open(_:completionHandler:) is also not working. All of the above are broken without emitting any errors.

I am seeing a similar problem: dyld[410]: Symbol not found: (_objc_release_x8)