Correct, but its not the definition of "pay to win" itself that is subjective. Its an argument of degree and not an absolute. How much pay to win is a specific person willing to accept before they change their stance on the issue. It becomes a reductio ad absurdum scenario. Everyone draws the line in a different spot, but the objective fact is: We all do draw that line somewhere.
The issue is many people only comment on the current pay to win topic being discussed. The real issue isnt just the one new item, but that the one new item is being tossed on a pile of already live pay to win mechanics that were inserted into the game in the past.
To a prospective new player trying the game out, thumbing their way through the DDO store, seeing how many items there are that allow them to get ahead of the learning curve (without actually learning mind you) this can be a major turn off.