Microsoft was given an ultimatum by the US Department of Justice to stop improving IE, because at the time people thought browsers and the web shouldn't be a part of an OS base install.
Microsoft started what Electron/Cordova/PWAs are continuing today, where the web is a first class application platform in nearly every OS, and nearly every OS needs to bundle a web browser as core functionality.
> Google, however, directly benefit from the web being a better place
…to serve ads. As long as the web remains the most universal platform for ad serving, Google's interests follow.
> now that there's (currently) a good compliance of standards and no such things as ActiveX
Let's not forget how recently Google tried to make NaCL, its own play at an ActiveX-like thing.
It's only recently we've "killed" Flash, and Oracle and others are still holding a lot of Enterprises hostage to Java applets.
Mozilla may be the only group without sin here, and they live in a glass house, to mix metaphors.
Microsoft had no desire to improve IE and make the web a more desirable platform than Windows. (I'd suggest it still doesn't)
Google, however, directly benefit from the web being a better place, and they know first hand that a dominant browser can be toppled. And the competition is fierce, with MS back to bundling and it's so easy to switch browsers now that there's (currently) a good compliance of standards and no such things as ActiveX.