On page 289 of the PHB for Wish:
The stress of casting this spell to produce any effect other than
duplicating another spell weakens you.
There are effects and uses for Wish mentioned through D&D 5e other than duplicating another spell. One example, on page 245 of the PHB, is for ending a Geas:
You can end the spell early by using an action to dismiss it. A remove
curse, greater restoration, or wish spell also ends it.
Would you be weakened when using wish in this case? If so, why would you ever use wish for this when you can achieve the exact same effect by duplicating remove curse or greater restoration?
Best Answer
Yes, it weakens you
As you quote, using the wish spell for any purpose other than to duplicate a spell of 8th level or lower will weaken you. This includes ending effects that explicitly say they can be ended by wish.
It is useful when you don't have to cast wish yourself
An NPC can grant you a free wish, and so can a magic item. In this case, the burden of the casting does not fall on the player. You would be able to simply wish the status effects away without needing to duplicate a greater restoration or remove curse. No intermediate step is necessary.
It guarantees the removal of the effect
Also, consider that including mention of the wish spell in various magical effects as something that can end that particular effect, means that the DM will be hard-pressed to try to twist that wish into something undesired. Wish is a dangerous spell, but an effect that is explicitly ended by wish provides no leeway for interpretative shenanigans. "I wish the curse ended on my friend" could kill your friend, if their death ends the curse, unless the curse actually is stopped by wish explicitly.