What will finally break the internet?

A quantum computer that can crack TLS.

Sort version, it would be able to read absolutely everything sent over the internet (so, bank records, etc.).

Edit: And to add further context, this wouldn’t just be a matter of using a different encryption. It has to do with the theory of how quantum computers could work differently from current ones. Basically, if the quantum computer can process data in a way that it theoretically should be able to, then it could quite rapidly crack any current method of encryption we know of.