I've always found those maps cumbersome to use, but I can see how non-radio people might find them beneficial. If you're just wanting to hear local stations, looking on the map might be easier than trying to find a list, especially since TuneIn's mobile app breaks out its local stations by format and popularity (and is usually wrong on a few). Plus, you can select the genre you want to hear on the map. Even if it's wrong here-and-there, if you want something similar to your local station and are just a casual listener, the map is probably more helpful than call letters or location. I will also say, from my standpoint, being 50 that my eyes aren't what they used to be. I was lucky enough to have 39 year old eyes for nine or ten years, but I've had a hard time seeing those maps on my iPhone the last couple years. I have a distance eye and a reading eye now, but it's not perfect technology, and I'm not going to carry reading glasses around when I'm walking the dog just to see the map when I want to change stations.
I was told Radio Garden did a few years ago, though I haven't used it in several years. You probably know more about it than I do since you seem to use it a lot more. If it has its own directory now, good for it.