It all comes down to the net number of additional subscriptions from implementing the jump potion.

Attracting new players without it, and forcing them to slog through dozens/hundreds of quests is daunting enough to turn away new subs.
Some existing players will quit because they feel betrayed for their loyalty, view jump players as somehow lesser, or for whatever reason.
# quitters < # new subs = jump potion good for SE (and I can't see this not happening).

How they decide to spin it to appease the current player base is up to them. It's a business. Let's not forget that.