I didn't think my internet connection was even capable of doing something like that... let alone from YouTube, which has a tendency to be slow and unresponsive late in the day (when I started this). I thought, surely this won't finish by the time I wake up... but boy was I ever proven wrong. I woke up and checked the status, and it was done!
Its likely YouTube have servers on your ISP's network, very demanding services like Netflix do too. So if your using something to rip video off YouTube you can probably max your internet connection out pretty easily. Depending on where you are in the world internet connections can be pretty fast these days, I could download 100gb in just over an hour. Sadly connections can also vary massively depending what street you live on, i know houses not so far from me that were stuck on 1-2meg until recently, where as people who lived on a street that was dug up for cable TV in the 90's could get 200meg.
Yeah, real-world throughput for my home internet connection maxes out at around 2.8 Megabytes per second, which equates to an advertised speed of nearly 22.5 megabits per second. Not bad, considering I only paid for 20. This test also shows that a wired connection is way more stable than wireless, which was repeatedly plagued by network errors.
Id never use wireless for anything more than keeping a mobile device connected, or general browsing on a laptop. At home everything is wired, I could manage without wireless to be honest as i generally use my PC for anything to do with the internet. Even at work the only real thing wireless is used for is on peoples personal devices and occasionally showing a customer our website on a tablet.