What do you suggest we do over this ? Forbid some people to search on Google ? Or give each user X queries / day then say "please use another search engine; here are some alternatives ...".
The laws are against monopolies abusing their power. As long as it's trivial to change provider we are in the clear; but the trouble come if a company uses their position to gain an unfair advantage. For example if Google says "You have to un-index you site from bing otherwise we will apply a ranking penalty on your search results".
But "being the default choice with a trivial switch possible" is hardly an abuse of power.