It's a completely different medium to be honest. Youtube is full of entertainment, but also there are thousands and thousands of great channels, from which you can learn amazing stuff. I remember that I used to watch videos explaining advanced maths when I was preparing for exams on YT. For example, I love Kurzgesagt channel and their approach for science. Books are something completely different, they are almost as old as civilization and it's difficult to compare them with YT. Both mediums can lead to some great knowledge, as well as - entertainment too.
But there are books that is written and copied tru internet so we can also access,and I believe that some of them are in YouTube also.
The thing is both are knowledgeable if we only know how to handle and to use them
So in this case we can have them on our side to learn many things