I feel like it's my duty as a chiptune artist to chime in here.

Chiptune artist? Dumb (but sincere) question coming from a total noob...

Is there an actual market for this?

There are a lot of indie retro stylized games, festivals like e.g. https://en.wikipedia.org/wiki/Blip_Festival

So kind of yes, there is.

Hi no9, and thanks for following up.

Would being able to write and produce this stuff contribute anything substantial to your portfolio or demo reel? Or would the majority of indie level designers likely not be looking for this type of material to begin with? I guess I'm trying to gauge how prevalent the retro design community is.

I already have a considerable background in subtractive synthesis in and all other music fundamentals. I can't imagine it would deviate too far from the rest of your skill set to learn, or am I mistaken on that? :D

It all depends on you and how you want to position yourself on the market. If you have strong bond to one particular music genre doing anything outside your spot can be dangerous. Or you can try to be as flexible as possible and make whatever game developers demand. There is no right single path to follow and taking into account the number of games that are released each year you will find any type of developers amongst their authors. It is all in your hands.

Devs are looking for all kinds of music as there's such a wide variety of games being made. And the target of what they're after often changes over years. Don't just focus on one style however, or you might really limit yourself... but you also cannot be a master of all styles. :)