I stumbled upon Toothfairy while searching for a way to prevent my headphones (Sennheiser Momentum 3) from auto-launching Apple Music when turned on. I am running Big Sur.
This is incredibly annoying. Strangely it doesn’t always happen, just sometimes. I do use Apple Music so decomissioning it is not an option.
Ideally I could prevent any desired bluetooth devices from auto-connecting on a case by case basis but this functionality is not explicitly described in the product description.