The actual line from the new terms of service that go into effect on December 10 is this:
“YouTube may terminate your access, or your Google account’s access to all or part of the Service if YouTube believes, in its sole discretion, that provision of the Service to you is no longer commercially viable.”
Give this some serious thought. What does your not being "commercially viable" mean?
If your channel is for kids, there will be no ads on it. So say goodbye to that money.
Also, does this mean YouTube may remove your channel if... say... governmental pressures force it to suffer losses?
In all honesty, this was a long time coming. YouTube has been famously (and allegedly) unprofitable for ages. You can't expect it to continue to foot the bill forever. Nothing is free. What YouTube was gaining till now was market dominance. Now that that has been achieved, it can change the rules.
The peril of building a shop on somebody else's land has always been this. The land may be taken away any time. And when that does happen, you will not be able to communicate to every customer that your shop has moved.
Never mind all the products you have sold till now with your present address printed on them.
If you have seen Stephen Colbert videos being recommended to you over and over again in the last few weeks, you know it has started already. YouTube is now a TV network.