Why have I not heard of Shriyantras? Why is it not spoken about that much?

Because it is so powerful, it could be used for the wrong reasons. It gives you so many siddhis. When you're able to traverse that journey from the Bhupura to the Bindu, you suddenly become a healer. So that is why the gurus, the rishis, have tried to keep this knowledge hidden. You know there is something called neuroplasticity, right? So this brings about neuroplasticity. That is why it is very important to meditate on theyantra.

Simply looking at it all- Even just looking at it brings about a change in the structure of the brain.