Aw c'mon, at least read the article and don't trot out a knee-jerk argument. It makes many valid points about how well Microsoft could really succeed in selling a Unix-hosted product when their heart was in Windows. Just by flipping the question around I think it buries the issue pretty well: If your Unix enterprise app needed a SQL server, why would you look to Microsoft?
Why wouldn't you? Microsoft is a major software vendor. If they make a solid DB for Unix, why not consider it alongside Oracle and other major software vendor's offerings? You would consider it on the merits of the product.
None of the reasons in the article make much sense to me except for the one left for last, that it just doesn't make overall strategic sense for Microsoft: Microsoft's model is pushing Windows, and selling SQL Server for an alternative OS is a bad idea (it's a good idea for SQL Server revenue, but bad for overall Microsoft revenue).
As others said, Gates would have veto'd SQL Server for Unix, that's the bottom line.
