I can confirm that the newest release of SmarterMail 16 doesn't work. I can't login to the system, see https://portal.smartertools.com/community/a89867/smartermail-16_3_6522-cant-be-accessed.aspx.
I think you're right that the product is getting worse and buggier with every new release but only since major release 16. There are a lot of issues with some absolute basic functions. Until 15.x I didn't had so many issues with this software. I'm using SmarterMail now for 7 years. In the past for me there was no need to have a test environment. With 16.x it's highly recommended.
And since some minor releases it isn't possible to answer the new release announcements in this community. SmarterTools seems not wanting to know which issues we have. And there are no answers from SmarterTools to issues which aren't solved for a long while!
There are two possibilities: Stay with SmarterMail 15.x or search for an alternative. I will stay with 15.x for the next time. But if SmarterTools won't change their policy regarding solving the issues and answering the threads in their community I will have a look for alternatives.
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