The SE mmo section had a fall of 22% according to
the last SE financial report. Sure this also include FFXI and DQX, but we know FFXIV is the main part of that section. The easy answer would be "because FFXVI", but FFXVI was released on June 22, at the very end of that period, it feels wrong to say it's the reason of that fall.
This follow the same trend we observed in the game. So there is fall of revenue, but its real amplitude will be only be see when they release the july to september numbers. But I would note it's the time period of 6.4, that acted as an eye opener for a lot of players, and the moment we began to feel that lack of retention. So Even the SE sales seem to support (or at least not contradict) the current narrative.