The question was which is the most likely to decline, not to disappear.

I don't think Facebook (or Meta) will disappear, but I do think it is the mostly likely to decline.

The only one I think may disappear is Netflix - this is because Facebook benefits from the network effect which helps slow any sudden decline as all your family are still on it etc. whereas Netflix just needs a bad run of poor quality content and it could lose a lot of subscribers to competing services.

Netflix is also less diversified (even though now it's adding Netflix Games for some reason.. we'll see how popular that is..) which further weakens its position.