The transistor radio sounds right to me in summer. Monaural AM radio reception changes with the weather, the temperature, the time of day, and just as we expose our bodies to the elements more in summer, it makes sense to me that audio should do the same. Plus, mono suits summer broadcasts so well: baseball games, violent storm warnings, the local oldies station (which plays mostly mono records anyway). How would stereo improve any of these?
I saw The Beatles in Mono box set at the library last week and checked it out. Not sure how many people know, but The Beatles saw stereo as a fad, and spent almost all of their time mixing their records in mono, leaving it to the engineers to make the stereo mixes. Brian Wilson mixed Pet Sounds in mono partially because he was deaf in one ear — he literally couldn’t make sense of stereo. (Mono also gave him control over what listeners would hear.) Later, Bruce Springsteen would mix Born To Run in a way that emulated that mono Phil Spector “Wall of Sound” style.
Related: Have you ever noticed how wonderful music from the first half of the 60s and earlier sounds on your tiny iPhone speakers?