The first part is important to signal that you aren't just trying to find people to work with, but that you also want to join up in a culture war, and a culture war requires promoting ideas to hate instead of letting them fade away.
Imagine how it would look if they wrote "no pushovers or girly-girls, please"
This may be because there is so much low quality stuff everywhere while only the good and high quality ones survived from the past (Survival of the fittest I guess). So the past looks like it was all good but the present is mostly rubbish.
But still, the thumbs are probably the least "handed" element of the body. I mix right and left thumb use based on whatever I need to be doing with my other hand.