I have mixed feelings about notes. They add a wealth of information, but they also break the pace of reading, turning it more into "academic" reading and spoiling the enjoyment. I remember reading "Romeo and Juliet" with extensive notes and I felt like I wasn't enjoying the text because the notes were always breaking my focus. So I just gave up on the notes and read the play by "feeling", it's actually not super hard to understand the text by "intuition", I'm sure there were things I missed but I enjoyed the reading better. With older books that have a lot of context that's easy to miss, I will research more about the book or specific situations later.
George MacDonald Fraser used notes extensively in his series of "Flashman" novels but I found that they were not necessarily pertinent to the plot so could be read even after finishing the book.