I can guess without reading: 1 ads 2 client side rendering. Youtube nowadays is 400-1000 kilobytes of Json + ~!8! megabyte of javascript(1). Pre Polymer (YT client side rendering engine update) you would receive 50KB of pre rendered pure HTML that would display instantly. Nowadays scrolling comments results in seeing them appear one by one while browser struggles with constant DOM updates. 1) >7MB desktop_polymer_inl…
Can you not.