Airpods pro audio quality is diminished when paired with my phone but sounds amazing when paired through my Apple Watch

So it’s just like it sounds. I’m playing music on Spotify on my iPhone 12 Pro Max with my AirPods Pro and the fullness of the music is diminished in the sound quality. I only noticed after forcing my airpods to play the music on Spotify through my Apple Watch (refurbished series 6), the full amazing sound quality (fullness of sound, reverb, and overall amazing quality) was amazing.

In comparison, when I go back to having them play my Spotify music through my phone, they sound like cheap headphones I just bought off the shelf at a grocery store.

What in the world could be the cause of this issue?