Haiku, you and anyone that agrees with you is an idiot. How do we know that you aren’t part of the eruv rav?? I think you likely are, because Jews are usually intelligent and you aren’t .
Firstly your stat that most Jews intermarried is wrong. Most Jews intermarry today, in 2019 that was not the case 100 hundred years ago, or even 50 years ago.
Secondly you focus on Chabad while ignoring every other outreach group there is .
Thirdly the answer is quite simple, they ask. Specifically they if your moms mom was Jewish. Considering the fact that in my case , my grandmother was referred to as Bubbie, spoke Yiddish, came from a shtetl in Europe and was elated when I went to yeshiva. I’m pretty sure of my yichoos.
With younger bts today, I doubt there was a vast uptick in the conversions to judasim during the holocaust.
Do some research instead of spending all your time in the coffee room spreading lies about klal Yisrael. It’s people like you that caused the golden calf. Shame on you’nnn