I wish CPLDs were more well known in the common vernacular.
The industry draws a distinction between CPLDs and FPGAs, and rightly so, but most "Arduino-level" hobbyists think "I want something I can program so that it acts like such-and-such a circuit, I know, I need an FPGA!" when what they probably want is what the professional world would call a CPLD - and the distinction in terminology between the two does more to confuse than to clarify.
I don't know how to fix this; it'd be lovely if the two followed convergent paths, with FPGAs gaining on-board storage and the line between them blurring. Or maybe we need a common term that encompasses both. ("Programmable logic device" is technically that, but no-one knows that.)
Anyway. CPLDs are neat.
I don’t know anything about this (other than doing mediocre in some undergrad Verilog classes one million years ago). Wikipedia seems to call FPGAs a type of PLD. Of course, everybody has heard of FPGAs; is it right to think they’ve sort of branched off, become their own thing, and eclipsed their superset?
I don’t see how CPLDs solve anything?
You write RTL for them just like you do for FPGAs, you need to configure them as well. The only major benefit is that they don’t have a delay between power up and logic active? But that’s not something that would make a difference for most people.
CPLDs are also a dying breed and being replaced with FPGAs that have parallel on-board flash to allow fast configuration after power up. (e.g. MAX10)