Linux is basically a big step backward for those two reasons plus others. This is more than a little bit disingenuous on Ed's part. People want to be able to use last year's version of Word to open a document created with this year's version. But Microsoft doesn't want that kind of integration. They don't want integration with competing products, and Microsoft software from yesterday is Microsoft's biggest competitor today.
Integration means never having to build it twice.
Once you create the integration infrastructure, interoperable widgets, and graphical doodads for your first product, all that stuff gets transferred over to your second product for free. Furthermore, because of the interoperability, the first and second product together have a value greater than the sum of the parts. Your costs go down, and the market value goes up. The difference goes to the bank. If you can control the integration framework, you can keep consumers who buy into it from straying off the ranch.