There's more than a few reasons why Linux can't make the jump to holding a dominant position in the desktop market.

One is simply preinstallation. For companies (and therefore the general public) to adopt the Desktop Linux, they'd need it simply to be installed for them, with a Desktop Environment like Gnome or KDE.

Secondly is updates. As much as Linux users tout the control they have over when and how updates take place, and how much Windows users will always complain about having to update their systems, until system updates on Linux are made automatic (or at least given the option to be made automatic), there cannot be a mainstream Linux Desktop. This means updates that happen very much like Windows, no administrator/sudo password, just happens on reboot regularly.

The reason for this is mainly that the average user would never update unless forced, and then when something inevitably breaks, they are left, as always, frustrated that their computer just didn't work as expected forever without any upkeep, understanding, or updates.

Lastly is support. And this is multifaceted. By support I mean software support by companies like Adobe. I also mean a much farther reaching swath of random devices that literally plug and play like on Windows.

As an aside, I'll also say that since there is a move towards Wayland, there also needs to be a No Configuration Necessary way of running Nvidia on Wayland. This is less a Linux issue, and more a Nvidia one, but until pretty much any and all hardware works on Linux the way it just works on Windows, this sadly affects Linux Desktop adoption as more and more of the Linux Desktop ecosystem moves towards forcing Wayland adoption.

Finally I'll say that the Microsoft corporation at large obviously relies mainly on Corporate Adoption of its products and services, and that the Windows Desktop is simply one part of that greater whole. Their approach to competing with Apple and their walled garden ecosystem has been to slowly but surely create their own, its just so much larger you forget there are walls. They have done this by absorbing more and more of the tech ecosystem either by acquisition, invention, or otherwise. Examples ot this include Bing and All Search Engines that Use it, the pushing of TypeScript into JavaScript Development, the predominance and proliferation of VSStudio/VSCode in modern software development, their heavy involvement with OpenAI and aggressive pushing of AI products/services, their acquisition of Github and subsequent further expansion of influence over software development and distribution, and much much more.

Despite the privacy invasion, enshittefication of the user experience, and their various other ways they have mistreated their users specifically via the direction they've taken Windows, Microsoft has established itself as THE Desktop, as THE Workstation, and as THE company that comes to mind when the average person mentions "computer", and the majority of people associate computer related productivity and play with Windows.

For all the advances made to Desktop Linux, especially in recent years, it is unlikely that Linux Desktop adoption will ever proliferate to the kinds of mainstream adoption that its accolades desire. Until Linux (or at least a Linux distribution) can demonstrate what I've mentioned above (preinstallation, automatic/automated updates, and wide spread software/hardware support from various 3rd party vendors) along with demonstrating a work flow/user experience that is somehow both familiar to the user and also better than the experience on Windows, then the day of the Linux Desktop will never come.

This aforementioned demonstration, btw, would have to become obscenely apparent to the average every day computer user who just wants to get their work done, play a Video Game, and watch Netflix, all without having to ever even know what a terminal emulator is.

I love Linux, and I think the Linux Desktop is not only a superior user experience, but is just better in general than Windows. But the average user I've encountered generally hates their Computer if it doesn't work as expected 110% of the time. Linux, and honestly computers, will never be able to do that, but the closer the Desktop (and user facing GUIs more broadly) get to creating that illusion of "it all just works all the time", the more adoption you'll see.