Which is regrettable when secure alternatives exist like Signal and Matrix whose business model doesn't involve selling your data.

Yeah I'm not saying I like it

For some egregiously loose definitions of "infrastructure," maybe.

The same definition that includes phone lines also includes the messaging service everybody uses

In parts of South America it's used for all sorts of things. Want to know when your bus is arriving? The bus company likely only knows because the driver is WhatsApp'ing them status updates.

And "important"