You can easily replace an IBM server with any other comparable x86 machine. You can't easily replace Snapchat and the user networks it hosts with another similar service.
My point is that as a class of product, Snapchat could disappear and not be replaced and no critical infrastructure would halt nor any innovation or science be stopped. At worst you would have some grumpy people.
It's silly to compare this to a product class that is crucial to our society and claim that it is better. The relative worth of one server to another is one thing, but the class of server products is infinitely more important than the class social picture sharing products.
Would you also say Facebook could disappear tomorrow without "any innovation or science be stopped" ? That seems like a silly way of determining if something has value or not.