IIRC, that would bring WDW to $18. Universal moved to $17 very recently. Disney is going to have to pay more than they are now, and do so quickly, or their staffing problems are going to get worse. The only question is how much. Given the exploding cost of housing in Central FL, even $18 is going to be tough to make do with, unless you are a household of two and both working.
And no, Dues will not go to "almost nothing" in the last few years, because Dues pay primarily for the ongoing operation of the resort. At best, the capital reserves amount will drop off, because at the end-of-life there is no reserve required. But at e.g. Saratoga, that's about $1.30 of the $7.33 total.