[1] Certainly not literally altruism. I suppose Google thinks this projects benefits everybody including themselves.
That's quite possible but once you start releasing unpatched vulnerabilities about competitor products there is at least a chance that 'including themselves' trumps 'everybody'.
It's not like we haven't been here before:
http://www.theverge.com/2016/10/31/13481502/windows-vulnerab...
So, google made a nice little 'hands-off' automatic disclosure feature which gives them a reason to say 'computer did it' but I don't think for an instant 'altruism' of any kind is the reason they do this.
If google really had the well-being of internet users at heart they'd shut down google analytics and stop accumulating profiles.
Until they do that my money is on Google estimating that they will do others more damage than they will do themselves through Project Zero and as such yes, we will all benefit but Google will benefit the most of all.
how would that "help" the well-being of internet users?
What's more, their analytics have nothing to do with the point at hand. Why even bring it up, except as an opportunity for a tangential soapbox? We're talking about disclosure timelines.
So if Google wanted to attack MS on the subject of privacy they'd have to go all the way to Skype to get some traction. So instead they attack on a front where Google is strong and Microsoft slightly weaker.
Google is anything but altruistic, their each and every move is to improve the bottom line for Google and their shareholders. If something is really altruistic it likely falls in their PR budget.