Earlier quoted context omitted.
They do. They reward sites that load fast. They also offer AMP as another way to speed sites up, which in turn makes them rise in rankings. But Google offers a large suite of tools to help web developers speed up their websites.
I hear this a lot, but whenever I search for something common like lyrics or weather, I get only large bloated webpages, while the lightweight and simple ones are nowhere to be found. Unless Google opens up their reasoning for ranking, I genuinely don't believe they add enough weight to load-times.
Obviously, there's many other factors at play. SEO is a complicated world, especially in such a crowded place as song lyrics. Though I noticed Google actually has an inline box for lyrics now which avoids the issue entirely.