I've been searching through the internet trying to find a concrete answer to my question, but I just can't seem to find it. The Incapacitated condition in my opinion, is written very poorly, because it leaves many open questions, one of them being, are you still able to move? And if you are able to move, how far can you move?
I've just recently come upon the Howler, a lower planes creature with an unique ability, the Mind-Breaking Howl. In the description of the ability it states:
The howler emits a keening howl in a 60-foot cone. Each creature in that area must succeed on a DC 13 Wisdom saving throw or take 16 (3d10) psychic damage and be frightened until the end of the howler's next turn. While a creature is frightened in this way, its speed is halved, and it is incapacitated.
So reading this one would conclude that you can still move while being incapacitated. Looking at the condition, it does state that the creature cannot take Actions or Reactions, the literal definition however states the condition as: deprived of capacity or natural power : made incapable of or unfit for normal functioning
To summarize I'll just repeat the original question, can you actually move while being incapacitated?