This was my biggest problem with G+ and why I haven't used it since last year sometime.
Facebook by comparison is a network of people you know irl, so you kinda care what random stuff they're up to.
G+ on the other hand is more like long-form Twitter where you subscribe to people, whether you know them irl or not. Its network based more on shared interest than real life connection.
But when people you've subscribed to because you're interested in what they have to say about programming start sharing their vacation pictures and other personal stuff, it can quickly fill up your news feed with noise.
It would be really nice if G+ could implement tagging and filtering by tag, or some ML that learns what to suppress in your feed from whom, or something along those lines. Anything to enable people to continue posting whatever they want, but to allow their followers to selectively receive only the portion they're interested in.