And, you're flat out wrong about the 'longest part' of applying for a job if you have to go through each company's individual "Job Applicant System" and fill out basic info over and over and over because the auto-fill systems are garbage 80% of the time. Redundant data entry is overwhelmingly the worst part, and Employers/HR people love to pretend that's not the case.
Let's say I've worked with roughly 1,000 people throughout my 20 year career. Let's say generously 20% of them I worked with closely enough that they know who I am and have a vague sense that I'm an awesome worker. 20% of those I've actually developed a friendly relationship with beyond water cooler chit chat, where we'd trust each other enough to be willing to help with a job search. Maybe 20% of those are now in companies where I'd want to work. And further 20% of that list are in positions so close to the hiring manager at one of those companies where they could actually speak up and have some influence on a decision. We're down to one or two people in the entire industry.
These numbers are guesstimates (pretty much match my own situation), but I just don't see how "networking" is the silver bullet everyone says it is. I'm sure when it works it really works, but I wouldn't rely on it.
Think of it like sales. Salesmen don't only sell to people they happen to run into at home or at the office. They go out of their way to target (ie: chat up and befriend) people who buy what they sell.
I couldn't find any data suggesting that it's true, but I did find this survey that backs up my assessment: https://www.linkedin.com/pulse/new-survey-reveals-85-all-job...
That said, I think you can apply to jobs with a single click on LinkedIn (and I assume StackOverflow?) so that has kind of been solved. Ish.