Recent and previous versions of Defender adds 2 to 3 seconds on first byte.

I have avoided defender for several months because everytime I enable it and do setup ti adds 2 to 3 secs to first byte delivery. Disabling defender does not fix the problem. Deleting defender does not fix the problem. I thought it was other issues using AWS and massive images etc but after testing with bare wp 4.7 and seventeen theme it is very clear that defender or the config it create is the problem.

YOU can setup your own test and do not need to access anyone's system.
My current Test setup but it happened with earlier versions of php.
Apache 2, Proxy Nginx 1.11.4, PHp 7.1, FPM app served by Nginx
Fresh wp 4.7.1
Test 2 or 3 times with http://www.webpagetest.org/
Add wpmudev dashboard
add defender
run defender setup but DON'T follow any nginx rules the have not worked in the past for me. I ignore them they are protection not performance.
Test 2 or 3 times with http://www.webpagetest.org/

You can also use
https://testmysite.withgoogle.com/intl/en-gb/
https://premium.wpmudev.org/wp-checkup/

Then responded to this trouble ticket after you see results.

thank you