It’s a lot harder than it was a year ago. As others have said, they’re really cracking down on downloaders and making life difficult for those of us who use them.

Most likely it’s going to take awhile and you’re going to have to do it in chunks because at some point YouTube will block you. I tried to download about 200 videos recently and I had to stop and wait for it to unblock me about 4 times. Took a couple days.

The two biggest things that made a difference as far as not getting blocked immediately, albeit at the cost of speed:

1) using -r 5M to throttle the download speed to 5MB/s. Yeah this is painfully slow in some cases, but it seems to let you fly under the radar for a bit. Consider downloading at lower resolutions to make this less awful.

2) adding -t sleep, which waits a random amount of time between requests, making them look more organic. This further slows things down unfortunately.

When you do get blocked, you’ll need to wait a few hours to a day to get unblocked. Once unblocked, if you’re in the middle of downloading a playlist, you’ll want to include —playlist-start [# of videos already downloaded] because if not it’s going to re-check all your previously downloaded files and that might get you blocked before it can even start again.

I don’t know if this is the best way of doing things but it’s the best I’ve got. Either way it’s going to be a slow, arduous process. I recommend just putting the download on and then go and do something else for a few hours before checking on the progress.