Hmm, I guess I see what you mean. To me the ads feel like an integral part of it, like the cash/card registers in a McDonald's, but when you point it out I see it can be a separate component. I suppose it would be like McDonald's manufacturing their own registers and refusing to sell them to competitors. There are a lot of register manufacturers, and a lot of other ad platforms, but indeed on other ad platforms you don't reach the Facebook users that you want to reach, so perhaps there isn't really any other option than to run Facebook ads.

I guess I also saw it differently because it feels like a free speech argument: why does FB have to give competitors a voice? But it's not about having to give someone a voice because they claim it should be a free (as in freedom) platform, it's for maintaining competition.

I think I've changed my mind. As you see I'm still thinking this through (out loud) but I suppose it should indeed be different entities, even if the to-be-separated ad business is selling "real estate" on Facebook.

McDonalds does actually do sponsored ad deals on its meals, with tie ins to major brands. If I remember right it is legal for e.g. CBS to not run ads for ABC programs.

It's been a long time since I've watched network TV, but I can't recall EVER seeing ads for a TV show on a competitor's network.

Hrmmm - well, I remember seeing HBO ads on all the networks. But your basic point is valid.

Did people forget the most recent case of this? "Disney bans Netflix ads from all of its TV channels except ESPN". [0]

Disney banned Netflix ads on its streaming service. How is that not the same thing? The monopoly argument crumbles when you realise how big Disney is compared to Netflix.

[0] https://www.cnbc.com/2019/10/04/disney-to-ban-netflix-ads-fr...