AV vendors totally mislead consumers because their products are not needed at all. Increased protection is already in Windows and nobody needs to pay for it.
Defender was exploited previously? is there any proof for that
Glad to know that! by the way, it's defense in depth, so to perform a realistic test you need to use all of the categories, not just Microsoft Defender. 
Here is a document about pentesting
[URL unfurl="true"]https://github.com/HotCakeX/Harden-Windows-Security/blob/main/Rationale.md#-for-penetration-testing-and-benchmarking[/URL]
Is there a PoC for that?
I'm interested in knowing full details about this
You did it with Administrator privileges? Because if you did then that's perfectly normal and it's not a vulnerability/bypass, as I explained in this document.
