I disagree. When not talking about a specific type of skill, general skill is determined by the ceiling imo. A higher ceiling means more room for improvement, so they’re a more skillful hero. You can put more work into them and continue growing. A higher floor just means it’s harder to pick them up.
For example, Tracer has a high skill ceiling because her kit doesn’t have any limitations you can’t work around. Everything you encounter that you can’t deal with is a skill issue. That makes her one of the most skillful DPS. But imo, a lot of heroes have a higher skill floor than Tracer. Until around Diamond you can get away with just having decent aim because it’s that much harder to hit you. Her skill floor isn’t particularly high because her kit is difficult to play into for bad players.