Conversely, from the perspective of people that started with computers in the 1990s, it's bizarre how Linux keeps failing to copy Windows. At one point something like 95% of PCs were Windows, and the rest were mostly Apple Macs. Similarly in the server space, you would be surprised to hear that the majority of servers were Windows for quite a while. Note that I didn't say web servers, because not all the world is HTTP.

There is still no equivalent to Microsoft Exchange, Group Policy, Enterprise PKI, and a bunch of other things in the Linux world. SAMBA copies Active Directory, but it's a direct clone, not a unique product.

Not to mention that SQL Server isn't somehow "copying" UNIX. Its performance and feature set blows most of the open-source databases out of the water, with only Postgres having superior features (but not performance).

Microsoft essentially invented OLAP with SQL Analysis Services, and they still have the most popular products in that space, such as Power BI.

Etc...