It is an FPGA; it can run synchronous logic operations. This could include something like the encapsulation of an entire gate and circuit accurate simulation of an entire system of processors, memories, and interfaces, like say, a Super Nintendo (see MiSTer for more of this). This is a very different domain than a raspberry pi, and while the chip here lacks the resources to run something like MiSTer it will likely be used to run something like a microcontroller SoC with customizable peripherals. The $25 price point for everything and the kitchen sink is just right. The comparison to Arduino is much more apt than to the Pi.
Not enough RAM. 640kB is actually enough for anyone as far as scalar variables in a single app are concerned so that’s what these small single task microcontrollers have.
