In other words: there is no investment in a corporation having rights added to it as if it were a legal person. The sole interest is that the people within the corporation do not have their rights subtracted by virtue of how they choose to organize.
You can see this in how people actually talk about moderation online: it simply doesn’t matter if it’s a corporation, nonprofit, union, or individual running a service.
I think a good way to think about it is as a leaky abstraction: for many purposes, it makes sense (and is very convenient) to treat a corporation as a person. It saves us a lot of ink! But that corporate person is not a natural person, so it doesn't have natural rights. Instead, it has only the synthetic rights that are extended to it through law.
In any case, the supreme court ruled it. So if they have personhood, they have a right to restrict speech on their own property. Unless, you think, I should be able to go to your property and put up my political sign at will.
The "endless amount of money" pumped is due to corporate personhood and an expansive definition of free speech rights.
This.
I think the problem is that on the whole, most people care more about outcomes than principles. And most people aren't very interested in constitutional issues. So most people find it quite easy to hold political positions that imply advocating two contradictory constitutional principles at the same time.
I include myself, by the way; I'm not pretending that I'm cleverer than everyone else. But at least I'm interested.
I come from a country with no (written) constitution, and I'm interested in constitutional principles. But I'm fearful of what might happen were we to adopt a constitution; basically I don't trust my fellow citizens to be able to think about these issues clearly. Constitution is essentially abstract law, and people find it hard to think in abstractions.
So perhaps it's actually better to think about these issues in terms of outcomes, and rely on judicial precedent based on concrete cases, rather than to try to distill principles from pragmatic judicial goals.
IANAL.
And they would still be able to make the documentary, they would just be subject to contribution limits.
Of course, like you said earlier, maybe they would have been fully illegal if the US didn't have a written constitution requiring lawmakers to think in terms of principles. It's a hard hypothetical to reason about.
People are concerned about money in politics because of corruption and special interests.
People are concerned about unmoderated social media because of extremism, conspiracy theories, misinformation, polarisation and all the impacts that has on society.
That's it.