When comparing ChromeOS vs Haiku, the Slant community recommends Haiku for most people. In the question“What is the best laptop OS?” Haiku is ranked 31st while ChromeOS is ranked 52nd.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro “Just a web browser”
On the other hand it’s pretty difficult to mess up “just a web browser”. You might get a few less phone calls from your elderly relatives about how they broke their fancy new email and internet machine.
Pro Android apps
Android apps add basic offline functionality.
Pro Booting & updating
Chrome OS boots from power off in about 7 seconds. So you don't need to leave it on and consuming power when it's not in use. You NEVER download and update any apps, although the OS does update itself. Web apps live on servers, so they're always up to date and virus free.
Pro Full laptop form-factor
Unlike tablets, the home of most hyper user friendly operating systems, Chromebooks come on an array of devices that don’t require you to buy any flimsy keyboard attachments.
Pro Pushes oneself to use (and learn how to use) cloud based solutions
With this ChromeOS also eliminates the time needed to configure the local environment.
Pro Very fast
Pro Beta has been released
After about 6 years since the alpha version, beta has been released on Fri, 2018-09-28. Check here for release notes.
Pro Only need 512mb ram
Pro Stability
Pro Runs perfectly on old Hardware
Cons
Con “Just a web browser”
There aren’t really any applications you can get on ChromeOS. If you can do it via Chrome you can do it on a Chromebook, but not much else.
Con No icons on desktop
Chrome OS does not allow to place icons or shortcuts on the desktop, only the background picture can be changed.
Con You might need a cloud printer
If you don’t live in the paperless world yet and you haven’t bought a new printer in the last three years you may need money up for a new cloud enabled printer.
Con No one uses it
It's a very niche OS that no one uses.
Con Unfinished
It's still in beta and quite unstable. Making it unsuitable for developing applications of any kind.
Con Language support is terrible

Con Small community
It is important when developing to be familiar with tools that other developers use. You can make any utility in any language you feel like, but if it's in an esoteric language that no one can read targeting a small platform that no one uses, then it was just something you did as a hobbyist, not as a developer.
This is not to say that Haiku isn't a great operating system to hack around on. Just don't delude yourself into thinking you're doing it to get familiar with tools that you need to know to be a better developer.
Con UI quite different to other OSes
