Allow On Access Protection needed with Defender ATP ?

Looking for more detailed info on Allow On Access Protection setting and should it be enabled ? 

We currently have Defender ATP and Realtime protection enabled, and  wondering if "Allow On Access Protection" somewhat redundant ?  

I've noticed explorer.exe  will crash and hang during certian senarios when right clicking on a .msi file to get property info. If I disable 'Allow On Access Protection' explorer.exe will crash less often. I have to disable realtime protection and allow on access protection to prevent exporer.exe from hanging and or crashing.  I do have a ticket open with TAC with crash dumps, so I'm hopeful for a code fix. 

But in the short-term, I like to understand the risk of disabling Allow On Access Protection with Defender ATP and Realtime protection enabled.

Thanks Roger.