"Today, there is a thriving ecosystem of payment providers offering a far more diverse set of features than a single provider could hope to. "
Bollocks. You could say the same about the android app store, but you still force users to use your own payment system.
Chrome apps were a horrible back anyway. They were a way to get around the shortcomings of the ChromeOS "everything runs in a browser" premise.
The security baked into ChromeOS is good. If they actually allow sandboxes apps to run, and ditch the browser-centric UI, then coupled with the already existing Android integration (windowized android apps) , they'd be onto a winner.
As it stands, OS configuration, even the SSH terminal are shoehorned into browser tabs. The obvious problems with that exist, not to mention the completely different UI for browser Vs android (and it's not due to touchscreen emulation.. The Android mouse interface does that well)