Not even remotely true.

You're making the exact same argument everyone here is making, and that's because you're attempting to argue from technical parity / superiority. Windows isn't the dominant desktop OS because of it's technical superiority to Linux, it's dominant because of deeply entrenched compliance and industry reasons.

Healthcare, finance, legal, engineering (less so today, but still very sub-discipline dependant), and government all have very specific software needs that no one in their right mind will bother writing new software, or rewriting existing software, would do for 6% desktop market share.

EMR programs (Epic, Cerner, Meditech), Practice management and billing, Tax and compliance, Legal discovery and case-management tools, Niche hardware and it's control software

This is all the realm of Windows. Most of these applications are Windows-only (Win32 / .NET / ActiveX legacy), they're only certified and validated on Windows, and they're only contractually supported on Windows.

Even if Wolters-Kluwer rewrote the entire CCH ProSystem fx suite for Linux, now there's recertification, regulatory review, vendor retraining, staff retraining, potential issues with auditors and regulators, etc.

There's currently no upside large enough to justify: Vendor finger-pointing, Compliance risk, Training costs, Downtime risk

It's negative ROI all the way down.

Windows has to become so bad that switching to Linux for desktops overcomes all of the above.