One people started using a phone as their primary computing device, the inconvenience of a larger device to carry around became less than the convenience of having a larger screen.
Futurama predates modern smartphones. In fact quite a lot of classic Futurama hasn’t aged particularly well for modern audiences. It’s still a fantastic show though.
For our kinds of uses, I completely agree. But for a lot of people, most if not all of their computer usage is done inside a web browser.
For example, my mum sold her laptop because she never used it and, being a nontechnical individual, finds a phone much less confusing to use and maintain than a laptop.
I hate it and I feel like there's a not-insignificant market of people that want to go back to small phones.
The Moto X (2013) was, in my opinion, the perfect smart phone. The curve of the back and the rubberized texture were so comfortable in the hand. Never once dropped it.
I drop my Pixel all the time because it's so light and thin and slippery. Drives me crazy.