You have a very small number of blocks of analog and digital functions that can be connected together in various ways. Cypress are not open source, but the tools are better than average (FWIW).
FPGA's are a pain because you get a gigantic quantum jump in complexity right away. For example--a system clock. Do you want a single one? Okay, now you have to deal with distributing that clock and dealing with termination and reflections. Do you have more than one? Okay, now you need to deal with synchronizers right out the chute.
For most hacker types, the Cypress chips are a MUCH better match to what they need to do. Generally these digital tasks break down into something like "Catch a very tight margin digital signal, respond with ACK and wait signal, and signal the core that something needs serviced." (example: communicate with a GPIB device) or "Have a tight feedback loop that receives slow commands" (example: PWM for a motor with an encoder).
The learning curve of FPGAs is steep because it's a completely different way of thinking. And if you're thinking about a particular application, I agree that the Cypress chip might be the best solution in a bunch of cases.
But the original question was which would be a good FPGA learning platform. I don't think the Cypress MCU are the best way to learn about FPGAs.
Similarly, your example of a system clock is only relevant if you're thinking about designing your own boards. That's even more beyond the scope of the question.
FPGA's are a pain because you get a gigantic quantum jump in complexity right away. For example--a system clock. Do you want a single one? Okay, now you have to deal with distributing that clock and dealing with termination and reflections. Do you have more than one? Okay, now you need to deal with synchronizers right out the chute.
For most hacker types, the Cypress chips are a MUCH better match to what they need to do. Generally these digital tasks break down into something like "Catch a very tight margin digital signal, respond with ACK and wait signal, and signal the core that something needs serviced." (example: communicate with a GPIB device) or "Have a tight feedback loop that receives slow commands" (example: PWM for a motor with an encoder).