Samsung has a rich history of alt OS maneuvers, most of them home grown or as part of a consortium. W10M is premade as a base saving R&D costs by limiting them to firmware. Cost to an OEM for W10M on a screen of 7" or less is free. Between the exploding Note 7 batteries and the exploding washing machines they need to make some highly cost effective moves to push their brand forward again in a positive light. It seems to be clear Tizen has failed to capture enough interest. Should they reinvent the wheel yet again?
Samsung is doing fine with Android. The exploding Note 7's had nothing to do with the OS. If they would have been running W10M they would have still exploded. And, I've read that many users burned by the Note 7 fiasco are eagerly waiting for the Note 8.
The long and short of it is that nobody wants a phone with WM on it. So what is your reasoning on why Samsung make it? "Look, the Lumia phones released with W10M took a year to become usable, and major apps are dropping like a rock. Sales are dropping like a rock. Looks like a gold mine!"
Their Android phones are selling just fine. Android is a well established, mature platform with a vibrant ecosystem. W10M doesn't check the box on a single one of these three points.
Don't worry; if Samsung thought they could make a dollar producing W10M handsets, they would do it. Why wouldn't they? The views by WM fans in this thread look like an attempt to rationalize wishful thinking. :eck: