Currently, the system can only stop sending messages if the contact opts out, or send an automated reply if the customer doesn't say stop. This makes it impossible to structure a system that has a default message to send to the customer if it doesn't contain the excluded keywords, without risking texting a customer that has opted out, or sending a general instruction message in response to a message that doesn't contain a keyword without messaging a customer that has just opted out. Simply adding the ability to exclude and include more than one keyword at a time, and allowing to assign a negative operator would fix this and improve the product quite a bit. It's an easy way to make the product much more flexible and robust, since it can cover a much, much greater set of use cases. Currently, if I want to create an automation even slightly more complex than one that can only reply to specific keywords without violating other rules is to pay for and use another service, and that seems absolutely silly given that it only takes a small change to avoid sending the customer to a different product. Also, I'm pretty sure this is extremely easy to implement, relatively speaking, and I can't imagine why this feature isn't built in since allowing Boolean operations is the default way every coding language reads a set of variables. I think you almost have to program this behavior out.
