I thought the same when I read "This was done (...) on a Raspberry Pi RP2350 chip, (...) for around 60p. Add the various extra parts (...) built today for a few pounds in one-off quantities. Call it the price of coffee and a cake in a European café today." "I opted for the Adafruit Fruit Jam (...)" ($39.95)

Unless you're paying $40 for coffee and cake I'll call bullshit.