Wow, I remember noticing this same thing back when I was exploring a lot of different artists. On streaming sites often a bands top songs will be ones that came out recently, or a collab they did with a more popular band, or a track that for whatever reason appealed to a wider audience. But those aren’t what you really want to hear if you’re trying to decide if you like that band. My strategy would instead be to go find either the bands earliest studio album or the oldest album that is well represented in their top tracks and skip to track 7. I never thought about why, but it definitely works.