No, the air has other ways of entering the house.

A drywall taper is the person who comes in after the drywall (plasterboard ) is hung and puts mud (spackling) on the joints and then seals the joints with a line of paper tape then covers the tape with more spackle

This is then allowed to dry , is sanded smooth and a second layer of spackle is applied

There isn't another name for spackling because it's a brand name

yes

The interior walls of a home can be roughcast using a product called Spackle. The Spackle is applied to the walls and then a special roller is used to move the Spackle around. Then the Spackle is allowed to dry. The walls can then be painted but only with an air gun to get into all the time spaces.