Last time I checked, these corporations did not control what everybody sees in the whole world. They control what people see on their platforms, and who generates the content on their platforms? Their users.
In practical terms, they collectively have the power to control what people see, more than any other single entity - Facebook alone has a global user count of 2.3Billion, there is nobody else who has as much control over what people consume, in terms of media.
That video you posted is interesting, because it's similar to something I pointed out ages ago, relating to the weird, backward policies of google image search and censorship, essentially - you have people making up rules as to who can see what - according to very strange principles and morals that I don't understand and to me make no sense.
Some things are ok - Alex Jones = BAD, holocaust denial = OK, soft porn = BAD, Islamic terror images = OK... so on.