Quite the opposite. I don't think any change is needed, and I was pointing this out by showing that a "legend" doesn't need to be the great heroic epic as some people here seem think they should be.
You didn't point out anything of the sort, and even if you had, you completely failed to show why something called "legendary" wouldn't be the stuff of legends. Other than some bullheaded determination to have your way with the vernacular.
In fact, you specifically pointed out that a dwarf could have tales told of him even if he isn't masterful in the task he's famed for. That if anything is an argument against having "legendary" as a skill rank.
Of course you are going to completely miss the point if you don't bother to process what you read. However, for your benefit I will break the concepts down.
Legends don't need to be world spanning epic. There are legends of differing magnitudes.
You get the great well known legends like the epic of gilgamesh, and of King Arthur. That kind of legend is certainly not the kind of legend a dwarf will achieve (Rare exceptions exist, such as Morul and Ironblood).
But you can also have national, regional, and local legends as well. The most basic is the typical legend of the old woman who lived in the burnt house on top of the hill, or outside town. Admittedly in the information age these distinctions have been breaking down, but in a fantasy world without an internet, where tales spread by word of mouth or letter, you can reasonably and justifiably claim that these distinctions still exist.
It is at this level that legendary skills would operate. These dwarves would serve as the foundation for local folk tales that reaffirm the commonly held values of the dwarves. Persistence, Industry, and the desire to contribute to community. Mastering any skill to the "Legendary" level serves this function.
"I want to grow up to be like Vucar Gatetrailed, who was so dedicated to his craft that when needed he could work a pump for a month without a break" is just as valid as
"I want to be as skilled as Catten Rungportals, who's skill with stone was so great that she could turn almost any piece of stone given to her into a work of marvelous beauty".
You are incorrectly assuming only the greatest of legends need apply, and ignoring the least, which is where almost all the skills lie.