Not purely negative. The doctor exposes his patients to some germs and have them create the appropriate antibodies. That's immunization!

There is a small interesting detail about IPv6 that is almost never mentioned. An IPv6 address counts 128 bits. Typically the "top" 64 bits are provided by your ISP and will be used to route the packets through the Internet. The 64 remaining LSb have to be unique within the subnet (typically a LAN), and usually these 64 bits are made from the MAC address of the interface linked to this IPv6 address (padded if 48 bits). That means for instance that knowing your IPv6 address, someone is likely to know also your MAC address (of the device used), that is usually the maker/configurator of the NIC (eg Apple, MS ...). And if the shop where you bought the device keep track of your MAC address - like Apple for instance - they may be able to identify you precisely, based on your IPv6 address (eg when you access their web site).

A software is not that naive. Software is made by people who might want to give some orientation to the way the software works. It's a software. But it's still made by human beings, and in an ideal world the software ratio malice / incompetence would have to be determined precisely prior to delivering any conclusion.

And other browsers as well... Safari is an Apple app, installed and updated from the iOS installations and as such has an unfair advantage in terms of OS resources. Just use and compare Safari and Chrome on the iPhone...