How would such a competitor be created and work? How would they gain sufficient market share? How do they gain influence in the standards organisations to push for changes they want instead of what Google wants?

If such a competitor were to use Chromium/Blink, how do they differentiate from the other browsers? How do they avoid changes that Google push into Chromium/Blink that they don't want? Where do they get the resources to develop standards they want to support like MathML or several of the CSS drafts?

If such a competitor were to create their own web stack, where do they get the resources and time to build the HTML, CSS, and JavaScript to a level that is competitive?