It was obviously huge. You could see it taking off. Yet a lot of people proudly displayed ignorance and backed each other up on it to the point that discussion around the topic was often drowned out by the opposition to change. Now today it takes minutes of playing with ai coding agents to realise that it’s extremely useful and going to be similarly huge.
Resistance to change is not a virtue!
Also, they were nothing more than the combination of two things which already existed, and which were already successful and financially viable: cellular phones and PDAs. In fact, I (and plenty of others I presume) already used that combination before smartphones: a PDA and a cellular phone, connected through Bluetooth to share the network connection.