Application icon on title bar in Windows 10

I am working on desktop software design currently where I got the feedback from the stack holder to remove the icon placed in the title bar of the application, with an argument that keeping icon on the title bar was in the guidelines of Win95 to Win7 UI guidelines but in Windows10, no icon is found on any application’s title bar.

As a UX designer, I think this is not a good user experience as it would be difficult for the user to connect to the opened application and he/she will have to remember and map the application with different icons he/she clicks from the task bar.

Please help me deciding what should be the best practice to follow for desktop software design that will be targeting Windows and Linux OS?

Jakob’s Law: Users spend most of their time using other applications/sites, and they want yours to work similarly.

Looking through my applications on Windows 10, none of them have a title bar icon.

I’m not saying you’re wrong - if you really want to know, ask your users. But from a laws of UX perspective, the most consistent choice across applications is to axe the icon.