The advantage of an online dictionary is pretty clear: fast lookup, more information and media for an entry, always updated, zero weight, sharable, free. In fact, for the purpose of looking up a word solely, I believe that there is no way a physical dictionary is better than its digital counterpart. In fact, all of the reasons of the link you gave cannot buy me a thing, except the number 6:
The sheer density of knowledge held in your hands, in print, is an amazing feeling. The nostalgia of a big, paper book is also comforting and uplifting.
An amazing feeling is definitely not what you care when you looking up the word. When you look up a word, you only care about getting thing done, not caring about getting yourself immersed to the feeling of curiosity. However, being curiosity is important, especially when you don't always use the language you learn. Even if you don't take the dictionaries down, when your eyes see it by chance, your brain will recall your memory related with that language. It can be about the country you have visited or a friend speaks that language, for example. Those memories are not directly help you improve the language, but it will help you to not forget it. You can think about the dictionary as a good ad, an ad not about a brand but about your memory. Or if you want your kids to get enthusiastic in learning the language, you can use the dictionary to "activate their curiosity", either in a passive way (just put it where they can see it frequently), or in an active way (tell them some related thing that you know).
Moreover, a definition in the digital dictionary is barely information lying in the screen, which is only perceived by your eyes. The paper dictionary can carry more characteristics that can be felt by other sensory senses: the weight, the texture, the smell of papers, the turning of the book, etc. You have to use other channels of perceiving besides your eyes and fingers to perceive it. This again cannot help you understand the definition easier, but it can help you strengthen your memory once you know the definition. However, I would argue that the best way to remember a word is using it constantly, and the amount of information contained in an entry and in other sources that contain the word is probably more than what your senses can perceive when using the paper book. Nevertheless, those information cannot make the nostalgia feeling.
The advantage of physical dictionaries is in these situations. Not just dictionary but any digital tool is very convenient and powerful when you need to get thing done, but it also means that it will be invisible when you don't need it. By contrast, a physical one is not that strong, but can help you to get motivated to do that thing, because we haven't evolved yet to get used to the digital tools. And getting motivated is a very important step to getting thing done.