Good call on not taking them. You're much better off.
If "anxiety" is a kind of genetic disease, where did it come from all of a sudden, and why in such numbers? About 1/3 of the US, is that believable?
I have felt "anxiety" for prolonged periods of time on two occasions:
1. About 6 months. I was in a program where I had to compete against very gifted people whose well connected parents raised them on good study habits, got them tutors as needed, and really cared about their educational and professional development. I had none of that, nor was I gifted with their high level of IQ. So I was just winging it in the dark, and there was the intense pressure of being humiliated by coming in last place (which was a very real possibility all throughout). The difference between me and them was visible in more ways than just scoring metrics. I became quiet, awkward, and it felt like everything I did around them was "wrong" in some way.
2. About 2.5 years. I worked in a politically charged environment with that was very, very passionate about "diversity, equity, and inclusion." By the time I left, I was the one of the only (straight) white males left. In every situation from getting coffee, to using the bathroom first, to who got rewarded for their work, I was expected to step out of the way and let the diversity, women, or the sexually weird go first or win the interaction. I was constantly walking on eggshells (such as when I described a car accident as "the black car hit the white car" and was then played with like a cat toy by the diversity). I had zero backup, and those above me took their side every time. What kept me there was nothing more than someone else not excommunicating me, even though they could at any moment with no proof and no contest from higher ups.
In both cases, the "anxiety" was not just some emotion I could blow off as irrational, but was in fact a correct and reliable biological feedback to my surroundings. Something big was at stake in an environment that depended completely on other people's high opinion of me. I was isolated, powerless, and unprepared both times. There was no way to improve my standing with the two groups because it ultimately came down to the single factor of who my parents were and not something I could change.
The "symptoms" matched what long-time anxiety sufferers described 100%, but only with how it felt towards the end when it was clear to the others that I was not in control of how things went at all. I was in those places long enough to feel like the tension was a permanent part of myself that was discovered from nowhere.
God help those who feel this nervousness constantly and believe it's a disease of theirs. Leaving the environments stopped the anxiety after a cooldown of a few months (over a year for #2). I can't imagine what kind of environments some of the people on anxiety forums must be in that keep that feeling held constant.