That is unfortunately correct, Reb! If you have to support IE, then the traditional string-based approach is what you will need to use. I should update that tutorial shortly to mention this as a note.
From what I’ve been tracking, IE is more dominant in enterprises who need access to some legacy tech that only IE works on. For consumers, the usage of IE is extremely low. Different metrics report different numbers, but the caniuse value of around 2.64% (which is from StatCounter) sounds more right than the 12% number that netmarketshare is reporting. StatCounter’s desktop browser share has IE at around 8%.
(Welcome to the forums, btw! )