> you could make the exact same argument about almost any tech device, like the iPhone itself

I don't think this is true. There was a massive appetite for the iPhone for decades leading up to its release, and there was no question that mobile was going to have a giant role in the future of computing. If you look back, most nay-sayers didn't doubt the value or utility of pocket-computers, but rather just that Apple specifically would be out-competed by established vendors.