Can you remember a time when we had better web browsers than today? For sure there's some anxiety about the future, but isn't the browser situation today better than it's ever been?
No? Opera is gone, all we have now is Firefox, Chromium and a bunch of Firefox and Chromium skins. Some of them also bundle extensions for extra features.
Opera was great because it had lots of conveniences built in to the browser as well as bleeding edge features. They often beat other browser vendors to implement features, and they had a pretty good developer tool stack.
Now it's a shell of what it once was.
Before there was Firefox, IE, Chrome and Opera which all had their own rendering engines.
think of it like this: instead of a browser vendor implementing a feature and then the rest playing catch-up, that same feature will now be available for most users, no matter who has developed it.
edit: spelling
It would not work for back-end features, such as WebVR or WebAR, for instance, or WebPay, or WebGL, or wasm. All these features need low-level support and low-level patches that only Google may decide to accept or reject. For the moment, Google doesn't seem overly interested in WebVR/WebAR, for instance, so it doesn't seem that any of the Chromiumlings will be competing on that field.