Earlier quoted context omitted.
So just to be clear, you're suggesting that Google use threats of blocking content providers from their other products, to strong-arm them into better licensing terms? There's a reason they don't do that, in any business. How do you think e.g. anti-trust regulators would feel about that?
Perhaps I wasn't clear, apologies. Not other products. Google is a video seller and distributor. They have a right to decide what terms they like or don't, just as Walmart does. As a seller of widget X, there's no way I'd accept a product with a license that says they could just take it back anytime for any reason. No sane seller should agree to that.
Now, the terms for the movie rentals / sales would definitely be negotiated between Google and the content owner. And Google could of course make your no-DRM policy a line in the sand in those negotiations. But why would the content providers agree to that? There's plenty of other competitive platforms they can (and do!) sell exactly the same content on, being specifically on YouTube's movie rental system won't make or break them.
And then we get back to your original proposal, which was clearly that they'd be using all their unrelated properties as (highly unethical) leverage in the negotiations.
If that's not what you're proposing, maybe you could be really concrete about what you think Google would be saying in those contract negotiations? "We will be selling your movies without DRM; if you don't agree then X". What exactly do you think X would be?