The CO₂ footprint of streaming is significant. That article is about video, and audio would be much less, but when you listen to the audio all day long it’s significant enough.
There’s also a privacy factor. To stream radio online with the same level of privacy as receiving a radio broadcast requires using Tor, which likely triples the footprint with the 3 encrypted hops.
W.r.t hardware, my DAB player is a multi-function device; not just a tuner but also speakers, bluetooth & USB. It’s the same speakers I would use if playing an internet stream. To improve reception the hardware to add for the antenna is quite simple: aluminum pipe, bolts, and coax… nothing that would generate more e-waste.