Youtube is one of, if not the largest video streaming websites in the world. I feel for the vast amount of powers it has as a website it is visually limiting itself from becoming a modern front runner in styles of websites designs as it has that much influence over other websites and designers just for how well known it is. There will also be people who would say the simplicity and the design will work for the most amount of people as people of young, old and in between of every type of person in the world will be using it and they all need to know how to understand it. As you move through the website to a smaller device the less important things disappear and the things that are more important such as the search bar for videos, advertising and suggested videos stay. On the left of your video search and logo design, which seems to be a alright place for it to be as the things inside it are less important and are rarely used for day to day tasks.