Why is Curry suddenly playing so poorly? Is it just aging??

Curry is playing so, so poorly.
Is there some kind of injury issue?
Or is he just getting old...?
If it is aging, his decline seems much more rapid compared to LeBron.
Curry's style doesn't rely heavily on athleticism, either.
So even if he were to decline, I thought it would be gradual... since his shooting hasn't died out.