Is "Jewdar" an actual thing?

So, I have a question for you guys. I’m hoping you can maybe answer it. Some background! I’m an agnostic atheist, and believe it or not, both of my parents are not religious either. BUT, my mom’s parents are both Jewish and my dad’s mom was Jewish, while his dad was Russian Orthodox Christian. Both of my parents are from New York so in addition to them both growing in Jewish environments, they grew up around a strongly Jewish culture being from New York.

They moved to Texas in the late 90’s for a job and then I was born in 2000, so I grew up vastly different from them. Both of them have repeatedly told me that you can “just tell” when someone is Jewish which I don’t necessarily agree with but then again, I grew up in a different environment than them. For example, they would say a name like Goldberg is a Jewish name. To me, that sounds like a typical Texas German name. A lot of the white people in Texas are German or Czech heritage. I remember a kid in middle school with the last name Barenberg and he was a very openly catholic German. He was also a paper white ginger with freckles which I would more associate with an Irish person than a Jew.

I would consider myself looking like your typical White person but apparently my physical features make me look somewhat ambiguous. My skin is white but I do have very dark thick brown hair thats almost black, with brown eyes. A lot of people have thought I’m Mexican, but I have actually been told that I looked Jewish, and it’s always been from Jewish kids! I actually had a Jewish girl tell me my nose looked Jewish! I was like what? You mean like the stereotype? I was honestly offended. Whenever I was asked that, I always told them, i’m personally not religious and I don’t believe in anything but I do have Jewish grandparents on both sides which they always say “that explains it”.

Thanks for your answers!