I'm afraid you failed to recognize the importance of the Linux platform. In my case, we support multiple clients with thousands of mailboxes and end user Windows machines.
Without support for Linux mail server (postfix+amavis) all these customers will switch to a different AV solution, both for their mail services but also for their Windows machines. They want one solution for everything.
Too bad, eset was great. Now it will just be a memory for thousands of users.