Suppose that you are sending out email to all of your customers, letting them know about a thing that you are sure they will want to know about. Then you decide to send it from a fake email address, one named "no reply" or similar. You have immediately eliminated a route for your customers to ask you questions about your thing.
What was the point of your announcement if not to generate interest in the thing? Don't do that.
Send your announcement from an account that routes into your customer support ticket system (you do have one, right? if you have more than five customers, you need a ticketing system) and prepare your customer support staff with a list of answers to likely questions, and a way for them to contact the experts on the thing.
Every time you close a method of contact, you lose an opportunity to talk to your customers. If you don't want to talk to your customers, maybe you shouldn't be sending them email at all.