The insulation is on the attic floor to separate the attic from the house. You want your attic to breathe to keep temps and moisture levels down in there. In a vented attic you obviously don't want to waste time/money insulating the roof.
If any ads are present below my answer or words underlined/colored, I do not condone/support/use the product or services listed/linked to, they are there without my consent.
17,000 dryer fires a year, when did you last clean the inside of the dryer near motor or the exhaust ducting?