There are a huge number of people who would disagree with Python being a "crap" language, and the irony is that the only language supported in the browser is js. You're missing a big reason Python is popular, and it is another reason this is a big deal. The number of people that have an opportunity to make web apps opens a great deal.

Also the idea is you CAN now access those libraries like numpy, even though Python speed in general is usually overstated.