Any pile of leaves, no matter which kind, is too much anyplace. My woodland garden gets about 4 inches of leaves from the trees growing there each fall and even that sometimes prevents some things from growing. 4 inches of shredded leaves on my planting beds is enough to prevern "weed" growth and if due care is not used when spreading them around could keep some of the plants I want from growing.

That is a lot of leaves. But, to look at it another way: where did the leaves come from? did they all come off the trees in the woodland you just transferred the leaves to? If so then it's not too many leaves, it's how much leaf material the woodland produces and you can expect it to process them all itself.

But if on the other hand the leaves came from trees not growing in the woodland, and the woodland is already producing as many leaves as it can process, then piling on way more leaves is going to depress the herbaceous understory. If they were soft leaves I'd be inclined to not worry about it, but oak leaves do take a bit longer to decompose than average. So they're still going to be around in spring when things are trying to come up.

Yes, they'll kill (at least temporarily) the wildflowers in the woods, and if you had native lady's slippers or trillium growing there, they'll probably be killed permanently. A lot of wildflowers depend on a very specific duff of a very specific makeup to survive. I would have bagged the leaves, piled them in a forsaken patch of woods, and given them two years to make me some lovely leaf mold.

Shredded leaves can be place in paths as mulch & will not harm the wild plants.
I plant trillium, may apple, bloodroot from grower, not collector.
I put a softball size rock or a metal stake to mark the plant.
That way I will not dig or cover it, in my old age.

I can't imagine having too many leaves. After mulching the leaves, I spread them on my flower and vegetable beds about 2 inches deep. What's left over I add to the compost.