Netflix productions do content placement. It's pretty sneaky and they do use social media accounts for shenanigans like fake posts on subreddits asking "What was that jacket in TVShow S03E04?" and another account responding with a link. Big brands with recognizable logos also do product placement on those. For fantasy shows they aim to own the merchandise distribution, but for stuff that happens on the real world there's always product placement and webpage placement and stuff like that going on.
I hardly see product placement as being even remotely close to what YouTube is doing. Its probably one of the most innocuous forms of advertising. Imagine a YouTube where the worst you can come up with is a guy drinking a coke during his video.
