In the US you either had unlimited SMS or no SMS plan at all, in which case you got charged for every single message, sent or received. But I remember having unlimited SMS as early as 2003.
If you had no SMS at all then you certainly didn’t have a data plan, which ruled out WhatsApp entirely.
That’s easy: unlimited SMS was common on most mobile plans in the US as early as the mid-2000s. Unlike the rest of the world, Americans had no financial incentive to use WhatsApp.
In the US you either had unlimited SMS or no SMS plan at all, in which case you got charged for every single message, sent or received. But I remember having unlimited SMS as early as 2003.
If you had no SMS at all then you certainly didn’t have a data plan, which ruled out WhatsApp entirely.