There is a rule of thumb
This is not the full story
A cooked turkey should be at 72C. When you take it out of the oven it will start cooling down. As it cools into the 40s bacteria will have good conditions to grow. The turkey is sterile because of cooking but bacteria can attach to exposed surfaces. Cutting the turkey will expose more, and probably your hands will spread bacteria.
It follows that a whole turkey is safer, especially if it is covered, since the inside of the bird will have no bacteria, only the outside.
So the 2 hour rule, which states a turkey rested for 3 hours must be eaten and not refrigerated is not really a one size fits all fact. But it's a rule of thumb when you don't have a lab and culture tests. Ignoring such rules is at your own risk but you can use common sense.
At home you might happily rest a turkey for 3 hours but in a commercial setting this could violate local laws if you kept the leftovers and someone got sick, you wouldn't have a defence and could be criminally liable for failing to follow defined rules. Most commercial health and safety rules err on the side of being more conservative than is necessary, because a dry turkey is better than people getting sick and suing you. Remember that bacteriology is about numbers and we might talk about 6.5D reductions (10^6.5) and McDonalds might use a higher level, and an expensive restaurant is almost certainly on a lower level as shown by many food poisoning cases in fancy restaurants. That's because McDonalds have a huge number of customers so even 1 in 10 million getting sick might be too much for their lawyers, whereas if you are cooking at home then you won't even eat that many meals in your whole life, so probably follow less stringent standards and get sick rarely.
