Anyone optimizing for Add to Cart or Initiate Checkout struggling lately?

Is anyone else running Meta ads optimized for Add to Cart or Initiate Checkout and seeing a major drop in performance recently?
In my case, the top of the funnel still looks relatively normal — ads are spending, clicks are coming in, and Meta is reporting Initiate Checkouts.
But the final conversions after the IC have dropped dramatically, even though the funnel and offer haven’t fundamentally changed.
I’m wondering if this is specifically affecting advertisers optimizing for mid-funnel events like ATC/IC, rather than Purchase.
If you’re optimizing for ATC or IC:
Have you noticed a decline recently?
Are you still getting good-quality traffic after the optimization event?
Did your IC → final conversion rate suddenly get worse?
Are Facebook and Instagram placements behaving differently for you?
Curious to know if others are seeing the same thing or if this is isolated to my account.