[mileza]

I think the 600$ price point was inflated with the Pi and the Arduino being used. Simply changing some parts for cheaper ones would have allowed to reduce the BOM cost and thus reduce the price. The author mentions this in his post.

Also seemingly not a lot of people paid 600$ for the sign, with a lot going for a lot cheaper than that.

[FractalParadigm]

That's a part of what the article dives into. For example the LED matrix hat they were using from Adafruit was probably the most expensive option they could have used at $25/unit, and the article gave examples of much cheaper (i.e. 10% of the cost) parts that would have done the exact same job with a little extra engineering time/effort. Replacing the Pi with an ESP32 would have saved money, but like the article mentions using a Pi wasn't entirely a bad idea considering the free marketing they got from the foundation.