From what I found, Apple's laptops are sligthly above average in terms of reliability [0]. Sqaretrade sells warranties though, so there might be some selection bias, but I'm not sure if it would benefit Apple or not.
I'm willing to assume the selection bias affects all brands in a similar enough way to call it even. The bigger issues is that this is 7 years old now, I wouldn't rely on it too much unless you're buying an 8-10 year old laptop.