Here is a simple suggestion for bot immunity  - may be it is an opt in at user level ..

- Only those who I follow shoud be able to comment or react on my notes .. In a way "follow someone" is a proactive permission to "someone"  to react to my notes - reply , quote , fork or like etc ..  Rest everyone can read .. 
- If someone want to react to my messages - they should first follow me .. and then I can choose to follow back .. 
- If you dont "opt in " then every time someone follows you , you auto follow back .. 

I know it is probably a protocol level change and it will reduce the traction (particularly for new users) .. but in the long it will help #nostr ..