Yeah I mean even hunters are happy when deer make it through hunting season. But the real problem can be a harsh winter which we obviously didn't have. I remember some really tough winters and it's honestly amazing they can survive through it and find enough food when there's 2 feet of snow and -30 temps. The corn feeders are basically only used when it gets that bad from my experience. But lots of other cool info here:

Winter Feeding of Deer and Turkeys - PA Game Commission https://www.pgc.pa.gov/Wildlife/WildlifeSpecies/White-tailedDeer/Documents/winter_feeding.pdf