Not only does a Google or Intel or whoever need to not artificially prevent competition, it has to ensure that its competitors offer actually good alternatives? How can you put a responsibility on a party for the capabilities of someone else?
Definitionally, companies without viable competitors are monopolies. Microsoft still has a defacto monopoly on PC operating systems as Linux isn't a viable choice for 95%+ of PC users. This market situation is extremely detrimental to consumers but isn't illegal.
Linux has many more features than Windows, gives the user more control, respects privacy better, and is free even, yet consumers choose not to use it.
How far must a company or government go to create competition where the behavior of both the suppliers and consumers indicate otherwise?