On this page I'll be giving my opinion on if certain OSes using the Linux kernel, should be considered Linux
While ChromeOS uses the Linux kernel, it makes no attempt to brand itself as Linux. Even if it did, it's so far off from any distro it doesn't even feel like Linux. Anything that restricts you as much as ChromeOS shouldn't be considered Linux.
Android also uses the Linux kernel, but is far from Linux. I haven't used Android so I can't comment on the feel.