Where have you been in the past 10 years or so? Chrome views the web as their own fiefdom, and web devs happily oblige. There are now dozens of Chrome-only non-standards that are presented as "openly built standards" and devs deride other browsers for not implementing them.
In case of Windows, there is no spec. There is no possibility of implementing another Windows clone (patents limit such clones). Wine exists, but was reverse engineered with great difficulty.
A scribble on a napkin does not a standard make.
A feature released in a single browser engine without support, consent, and against objections of other browser vendors does not a standard make.
Just because Chrome ships something does not make whatever they ship a standard.
> The documentations and specifications are available for free.
That's how Chrome abuses its position and relies on gullible devs to assume that just because something is documented it becomes a standard the moment it's shipped in Chrome.
That's not how standards work.
The OS lock-in is much more difficult to break than Web where the standards are openly built and made available. One aspect in favor of Google is the complexity of implementing all those standards. But that is not lock-in, rather an issue of having enough resources to implement a compliant browser.