Implication: Want your ads shown to people? Don't risk another provider, serve them through Google.
Essentially, I believe Google and a subset of their industry competitors (other ad networks) have two goals here:
1. to stem the losses imposed by 100% ad/tracking blockers, by providing a default blocker that deals with very obnoxious ads that might prompt average users to install one of the existing ad blockers.
2. to reduce their need to pay protection money to AdBlock plus etc.
So, if you happen to be using ads that are overly obnoxious (popups, autoplaying videos, etc) then yeah, your message is basically what they're saying, but not because it's non-google, just because it's making the other ad networks look bad.
I don't know how they'll implement it technically, but the fact that they are not talking about the WebKit-style content blocking using compiled pattern lists means they probably have little interest in benefitting end-users (webkit content blockers give better privacy, performance, battery life etc, compared to traditional "run this code every time a website loads" blockers)
> The ad-blocking feature, which could be switched on by default within Chrome, would filter out certain online ad types deemed to provide bad experiences for users as they move around the web.
> Unacceptable ad types would be those recently defined by the Coalition for Better Ads, an industry group that released a list of ad standards in March. According to those standards, ad formats such as pop-ups, auto-playing video ads with sound and “prestitial” ads with countdown timers are deemed to be “beneath a threshold of consumer acceptability.”