I also sound cranky a lot lately when complaining about loud or unwelcome sounds in public spaces. So this project (and your comment) resonates with me.

Also yes, hiking with a bluetooth speaker is particularly galling. you're in nature! For that reason I've been considering buying (or building) a portable bluetooth jammer. I wouldn't do all the time, no reason to punish someone using wireless earphones respectfully. It'd need to have a trigger for JIT intervention.