I was always told "It doesn't matter who you know. What matters is who knows you."
Well, just stumbled upon this, just my 2 cent after working in the industry for so long and have even hired people in multiple occasion.
Whoever that hire people for work are just people like you, they are influence by recommendation, and any potential factors that could help them make a better decision. When you are a fresh graduate, the strongest criteria for comparison is your education result, followed by interview result and so on. If your education score is below average, you don't even get a chance for interview, that's just how it works. Phd is not exactly a good metric for hiring when it comes to higher skill level jobs, for that, a lot more factors are in play, specific to its own industry and job position, recommendation and knowing people are important when it comes to management jobs, but so are technical skills and achievements in different type of jobs.
If you are studying, don't take stranger excuses to not work hard.