Sure, but competition is good for the user.
My reply is: the software has no known bugs, therefore it has not been updated.
The Postfix security model is based on keeping software simple and stupid.
Lack of documentation is becoming a problem for acceptance.
At the time the Sendmail program had a very poor reputation with respect to security, with four root vulnerabilities per year for two successive years.
Windows favors multi-threading, which means that a service is implemented by one single process.