Earlier quoted context omitted.
The ChromeOS equivalent of LineageOS is usually just installing a normal linux desktop distro, sometimes one that's been been tweaked to have drivers specific to chromebook hardware like GalliumOS ( https://galliumos.org/ )
I don't think "a normal Linux desktop" matches the same target audience as those who would wish to run ChromeOS
Keep in mind, Google's reputation among hackers has dropped a lot in recent years. Trying out an operating system where the core premise was "you spend 95% of your time on your netbook just in a browser, why not optimize for that and strip away the rest" was an intriguing proposal. This was back when doing things in web apps instead of desktop apps was new and forward-thinking, not totally overdone the way it is now.