Incorrect. You've always had to have an AdSense account as that is what tracks your earnings from the ads on YouTube. Networks then take that information (and money) directly, take their share, then you give you yours. I've never known a network to not do this.
I wouldn't recommend joining a YouTube network unless you've got 1 million + views on each new video you upload to your channel. Of course, you can do as you wish here. I'm just a nobody offering my own personal opinion. But, ask yourself and ask the network before jumping on the ship what they have to offer you. If your channel is small, what are they going to do for you to help you grow? How will they help you grow? What are they offering you specifically that will help you and your channel improve?
Are you partnering just for money? If so, you can monetize your channel without a network and get more back from your channel than with a network. A YouTube network will always take a % of your earnings from your channel. Whether they do something for you or not, they get that % as long as you're partnered.