Looking for Second Opinion on New Insulation in Attic
What he's suggesting would be to make the attic inside the building envelope, therefore you'd be heating and cooling the attic along with the house.

You either need insulation at the attic floor or attic ceiling. One or the other is the building envelope. If you google some of the terms you can learn a lot.

If the house is a standard, single open roof I'd vote for keeping the insulation on the floor.

Maybe get a few more opinions?