Request: Add Time-Based Messaging Triggers similar to Chat

Currently, we have chat-based triggers (e.g. after 3 minutes of no reply), and we are considering switching to Messaging completely.

However, it seems that we cannot do a similar trigger with messaging and can only rely on hour-based Automation. If I have no agents available or they are busy enough that they don't respond in e.g. 3 minutes, I would like to be able to create a trigger to send an additional message to the end-user.