This depends on your circumstance and its important to be a bit more cautious if you received a large lump sum (e.g. from a disability settlement) that you expect to need or live off.

Yes the average person randomly assigned a lump sum on a random day will do much better if they deploy it immediately. But the tail person who gets the bad roll of the dice and receives it on a bad day will do much worse and may not have the money they needed to rely on.

You're not the average person, you're just one person from the population, and you don't know if you'll be the one with the bad roll of the dice or not. That's why people DCA.

If receiving a large lump sum like this you need to live off, either DCA over 12-24 months, or make sure you have some really good tactical allocation system that moves you to safety in the first few years.