The primary purpose of Google is to stop that. You have 100% trust in Google results because of the effort they have put into cleaning the results you see.

Billions have been spent on it.

Try searching Bing sometime. First result for Firefox is a malware clone site (you’ll have to scroll past the malware ad to see it).

The frequently incorrect or misleading Gemini answer at the top of search results is busy eroding that trust.

People will have varying levels of trust in Google, but 100% is clearly too much, given the quality of results.

This is completely and utterly wrong. Google may put some effort into catching malware - but even that is limited to the more obvious cases. But for almost everything else, they put between 0 effort and negative effort into trustworthiness of the sources (e.g. they clearly favor big businesses for certain product searches regardless of quality).