How to disable automatic Bluetooth connectivity?

I own multiple sets of Bluetooth earbuds, headphones, and speakers. Whilst I am paired with one set or speaker, often times my iPhone(15) will discover another set or speaker and the sound will be interrupted. It seems the only way to stop this is to forget the other devices I have stored. If I only disconnect from them, it happens over and over. Super frustrating! Especially when listening to an audiobook overnight, or music when I’m working and my phone is out of reach. Shouldn’t there be a simple way to disable Bluetooth from searching when it is already connected?