I had the same thought as you. I sent a general letter of concern to support. Below is the response I got. I hope that it means they are concerned and take action [ if some of their customers are getting blocked then it’ll be in their financial interest to resolve it.]
This is just a notification that your message has been moved to our mail blocks queue. This queue is information that our abuse staff uses to determine who is blocking us, why we are being blocked, and at around what time period we are being blocked. Your ticket will be used for information purposes only in helping us get the block removed. You may not receive a response, but you will be instrumental in helping us get this issue resolved faster. Thank you for your mail block report.
The Dreamhost Ticket Moving Robot!