The reality is that for most people, they use an app on a sibgle platform (typical end users don’t constantly switch between Windows, Linux, and macOS) so that consistency does not primarily benefit the end-user.

Exactly. The consistency being extolled here is not from the perspective of the users but of the marketing department that wants to warp basic UI conventions in service of making their branding a more pervasive part of the user experience. Users basically never want you to give them an app where even the buttons and scroll bars are changed to comply with your corporate style guide.

On the other hand, if Google Docs had system-native controls for every useragent that could connect to it, nobody would have any clue how to do anything and search for a new online document editor. It's not the overwhelming love for Material design that makes Google Docs look non-native, it's the experiential consistency for enterprise customers and less computer-obsessed end-users. If that amounts to sacrificing usability for branding, then Apple is just as guilty. Design is just part of building a product, and prioritizing your specific OS is not a realistic expectation from cross-platform products.

And for professionals, I don't even wager this consideration takes place at all. I don't see anyone protesting Ableton Live or Pro Tools because their developers didn't use the native MacOS button widget.

People are more than happy to use Microsoft Office…?

I couldn't think of a more branding-heavy native app. It's got the ribbon interface of Windows ported to MacOS, the rowed toolbox with different button sizes, the status-bar on the bottom, it's still basically a Windows app with MacOS widgets.

And generally speaking, yeah, people are happy to use Microsoft Office. The Mac version is nearly identical to the other versions. The "branding" is ignored or even applauded, because it enhances the overall consistency of the app. You might even be able to argue that Office on Mac only feels native because it goes out of it's way to not look Mac-native.

Regardless though, for non-Microsoft-sized companies it's not really realistic to ship, test and maintain multiple versions of the same app. It's much easier to pick one cross-platform framework and commit to it whole-heartedly, which is why we really only see native apps for single-platform or Microsoft-scale apps.

What is Google if not a Microsoft-scale company

What is Google Docs if not a perfectly acceptable Microsoft Word replacement?

The acceptable replacements would be Libre/Open Office, then Pages. The latter has more feature than Google Docs. Where Google Docs shines is when you need collaboration and basic Word processing features.

I remember raging with our designers over this, when building a mobile app. They were insisting on controls that look and feel exactly the same on iOS and Android because of some vague need to have consistent marketing/branding. Which ultimately meant custom controls (sometimes 10x development effort) that were not familiar to users on either platform. No user wants this. It's desired entirely by companies whose design department is too focused on their own designs.

The same is true for desktop applications. No macOS user wants their application to look like a Windows application and no Windows user wants Mac controls.