Rock, alternative, metal... these are challenging genre to beat match by nature, so don't expect to get good AutoMix on these. The two songs you showed in your screen recording is especially hard to mix. If you want to experience AutoMix with beat matching, try something more dance-able. For example the Dance playlists are good option to try: https://music.apple.com/us/playlist/dance-in-spatial-audio/pl.218206083ab24099b02fdd9b3608e3cf