The reason this road is primary is that there is no corresponding interchange to 3300 S from northbound I-215 to the one from southbound I-215. 3300 S is the primary road in the area, and this part of Wasatch Boulevard serves as the access to 3300 S from I-215. Reverting this change as it breaks this primary connectivity (and the related change that upgrades 3900 S to primary since it doesn't serve a primary function here)