Power
There are three real ways to influence others. The first is with science, e.g. "the tomato is a fruit because it developed from the ovary in the base of a flower."
The second method is brute force, or "you'll accept that the tomato is a fruit or I will crush you."
The third influencer is celebrity: "I don't think the tomato is a fruit because, like, whatever. #notafruit #omg #amirite. "As a YouTube personality, you'll likely fall comfortably into the third camp, though hopefully you'll be a bit more eloquent than our imaginary celebrity friend.
Maybe what you say will make sense, maybe it won't. But because people like your videos, some will blindly take your word for it whenever you say crazy stuff about basically anything, whether or not you're qualified to have an opinion on it. Fame is funny like that.
A YouTube personality has some sort of power, sure. And like any power, you shouldn't take it lightly. You'll need to be really super-duper famous before you can have any mega influence or power. When it comes to bending gullible people to your will, though, a little can go a long way.