Google may focus on specific types of exploits, but they let everyone bad just walk right in the front door.
Assuming you know better than installing adware or installing random chrome extensions, Chrome is the most secure browser out there.
Btw, regarding extensions, before Mozilla switched to WebExtensions, you could do nasty stuff like extension-reuse attacks.
You can hit a single accidental click on a malicious Google ad (yes, there are many), and end up with a voice telling you to click the "Install Extension" button to regain control of your browser, which alternates between a JavaScript alert popup message and the extension installation prompt to make it hard to get out of any other way (it's doable, if you're not a layperson). Approving it installs an extension which can inject ads into web pages and collect data on everything you visit and anything you type into Chrome.
Sure, it's removable, but most of the victims of this behavior don't even know what Chrome extensions are, much less how to remove them.
This is absolutely something Google has failed to address, and it's really not accurate to refer to Chrome as "the most secure browser" while this is so rampant and unhandled.