No, it's impossible. Antenna theory dictates what the size of an antenna can perform at. Without significantly reducing the noise temperature of the antenna much farther than anything else out there, it will never happen. And noise temperature is pretty much guided by physics at this point.

He's saying we might soon have pizza-sized phones.

Ah, that's more likely :).

I'm not a hardware guy, but i doubt it. They would need to reduce the size and power requirements by an order of magnitude each of which we are currently struggling to do nowadays. Most importantly though, the wavelengths they are using i do not think penetrate buildings well and I don't think any of other wavelengths can effectively transmit that much bandwidth through buildings from space efficiently/economically.

Not only that, but phased array relies on the radio signal hitting different antennas at different times. So the array of antennas have to be spaced a minimum distance apart depending on the wavelength used.

No, elcritch is saying that phones will be the size of a pizza box in a few years.