im sorry but you dont have the answer to the question, you are making an assumption based on the information provided. You have come to the same conclusion as i have but i wouldn't state mine as fact since i don't know what the devs have planned
I don't have the answer to the question, the developers do. They posted the answer already. It is stated quite clearly in the text, but I will post the relevant bits here to show you that I'm not speculating.

Under Section 1. Class-Specific Actions
Upper tiers of an action (such as Fire II and Fire III) will be abolished in favor of a system wherein potency and MP cost are scaled based on the player’s level.
Under Section 4. Setting Actions and Traits
All traits will be made class-exclusive.
Adjustments will be made so that certain actions will only unleash their full potential when paired with traits belonging to the same class.
Under Section 5. The Influence of Levels on Actions
As mentioned under 1. Class-specific Actions, upper tier actions will be abolished in favor of scaling the potency of the base action according to level. The effectiveness and MP cost of the action will be dependent upon the level of your current class.
Those 3 bits answer the question quite thoroughly, along with answering the followup question, "Won't that make a Gladiator Cure at level 50 just as good as a Conjurer Cure at level 50?" (The answer to which is a resounding no). Please refrain from accusing me of making assumptions. I will engage in speculation from time to time, but when I do, I will not state it as a fact. The only assumption that I have made is that the information contained in Triairy's post is accurate.