I'm not sure how far back the saying goes, 'it's not what you know but WHO you know', but I'm positive it predates IT.
"Unfortunately, connections are a big deal in IT"
Why is being social and being able to network with peers an unfortunate requirement, unless of course you are a hermit looking to enter the workforce and have a little 9-5 cave with separate entrance from your underground parking stall?

"and even more unfortunately, it means improvements and promotions are based on who you know "

Are you brand new to the workforce?
Even labour jobs with unions are filled by people who knew someone that got them a job, has been that way for centuries.

Why is this new and unfortunate to you and yet so common for anyone else who has ever had a job? If you think it's a new development that's IT specific, you have a lot to learn still.

I just don't understand why having social skills and networking skills would be seen as an unfortunate precursor to employment. How else would you expect to get a job?