> You can see how this gets fuzzy then, right? At what point is a corporation "giant"?

Maybe the exact point where a corporation becomes integral enough to society that it needs to be regulated to protect people's rights is ambiguous, but it's not really ambiguous that YouTube is far past that point.

And I'm not being ambiguous at all about corporations not having rights. Limited liability has to be balanced by restrictions on what an LLC can do, or there's no incentive for people to act sociopathically (which they do). This is true at any size, and corporations violating the rights of individuals aren't limited by size. However, issues with small corporations are both less concerning and more likely to be handled by market forces.

> How to measure and who decides that?

Traditionally it has been regulatory bodies such as the FTC or the FCC. Congress typically hasn't made laws that target specific corporations or small groups of corporations, instead leaving that sort of micromanagement to the regulatory bodies. There are pros and cons to regulatory bodies versus congress handling these things. Ideally I'd want it to be elected officials so that citizens get more direct control.

"Measurement" isn't really applicable: you're looking for a size that can be quantified, but I'm talking about human rights violations.

> Why is it okay for your Dave's Liberal Hosting Service to arbitrarily moderate material but not YouTube?

I already covered this:

"If I started Dave's Liberal Hosting Service with just a server and a dream, and only hosted Democratic websites, that's fine, because such a service doesn't become the platform of the internet that everyone is forced to use--it's likely a conservative equivalent would arise even before I built a significant business. Part of the problem is that services like Reddit and YouTube have performed a bait-and-switch--they built themselves into major platforms on a free-speech ideology, and then when they were too big to fail, they turned into ideological platforms."

> Both YouTube and Dave's Liberal Hosting Service are still made up of individuals, and you think that individuals should be treated the same. So why aren't they?

Neither corporation has any rights: there's just not much reason to drop the hammer on Dave's Liberal Hosting Service if it's small enough that competitors could arise easily to meet need, and they've not banned any existing users. All the users who Dave's Liberal Hosting Service would "discriminate" against are already using Bob's Conservative Hosting Service, so free speech is available to society.

There are really only two household names in the video hosting space in the US, YouTube and Vimeo, and both of them ostensibly support all content, but don't actually live up to that promise. Not only is free speech not available in that space, but it used to be (at least, moreso), so previous users have had their channels taken away from them; their best options at that point are basically starting over if you've built a channel. If YouTube had started with the promise of censored content, they would have grown in tandem with competitors with more permissive content policies, and this wouldn't be the problem that it is today.

Both corporations are made up of individuals, but when they're acting behind the veil of a corporation and in fact decisions are being made by only a few of those individuals, while they trample the rights of the rest of the individuals that make up the corporation. If you're going to appeal to the idea that people shouldn't be forced to host content they don't agree with on a platform they built, you should realize that it's very unlikely that the engineers who built YouTube are the same people as the executives and board members making the decision to censor their content. The larger the corporation, the more disconnect there is between the individuals that make up the corporation and the actions of the corporation. With corporations of YouTube's size, claiming that individual rights confer rights on the company just doesn't hold water: you're only conferring rights on the decision makers of the company, at the expense of the rights of workers who devoted their work to older policies and may not agree with the new policies.