How is Blakley's Secret Sharing Scheme perfect?
Okay so SEJPM's comment just gave me an answer or better made me realize my flaw:

Since the secret is only one coordinate (e.g. $x$) the information that the secret is on a specific infinite line is as much information as having none at all, since guessing $x$ of a point on $y = 5*x$ is worth as much as guessing $x$ of a point on $y = z * x$

The information would only be revealed if the secret would be the entire point, not just one coordinate.