You should do this more often! I found so many great obscure songs just by listening to the radio and heard weird covers and alternate versions and remixes of songs I like. Gotta find the good radio stations which can be hard, but any college or high school run radio station is usually good if there are no local independents. Keep Shazam on hand or even in passive listening mode if that doesn't weird you out.
This one I heard on the radio ten years ago and was like wtf is this bc I love Daniel Johnston but to this day this isn't available on Spotify or anywhere but YouTube afaik. And if you try to search for it all you get are results for his other song Casper The Friendly Ghost which sucks
Another one that's not on Spotify. Heard it on a college station playing random songs, the DJ introduced this one personally and said how they found it but IDR
Also, if you listen enough and are lucky, on very rare occasions, you may even be shocked to find yourself enjoying a new, current artist......