If a such a highly publicized Google product is only used by "several friends" years after launch, it should be killed--not spammed more into the faces of users that do not want it.
The "several friends" I contact through Google+ are actual friends that I actually contact routinely, unlike the vast majority of the 200 or so friends I have on Facebook. Maybe I'm just unpopular, but I don't have more than a dozen actual close friends that I communicate with routinely.
Maybe he's talking about the ads, not plus. If the recommendations are just for people in your "friends" circle this recommendation engine has minimal impact. And just because I circle some people in Plus doesn't mean I want to see their recommendations.
I have my Facebook settings fairly well customized so that I only see updates from my closer friends. My point was that "several friends" is not a meaninglessly small number for a social network.