The consensus seems to be that everyone is slowing down with their software acquisitions. That could merely reflect the average experience level on these forums - most of us here have been at this digital audio game for at least a decade. Eventually you accumulate all the essential tools you really need, and over time you experience enough disappointments to realize that the promise of a new plugin is rarely fulfilled. If, after a decade or more, you're still burdened by GAS, the reasons are emotional rather than logical.
I think it's like gambling.
Everybody gets a thrill when they win some money gambling. Everybody's bummed when they lose. Whether or not you become a problem gambler (or a non-gambler) depends on how big the thrill of winning is for you relative to the downer of losing. Some people get such a high from the win that they forget about all the losses and illogically pursue that win rush, improbable as it may be.
My weakness is virtual instruments. One in ten will become standbys and the source of creative inspiration. The other nine will mostly just take up disk space. (1:10 is still better odds than a slot machine, though.)
The trick is learning to identify that one in ten in advance. I haven't mastered that yet, and maybe never will. I'm such a sucker for great demo songs, which really only demonstrate that a good composer/arranger/mixer can make something good out of anything.