If anything but lands count as spells can mindbreak trap count as a boardwipe fir the opponents if you want
Spells only exist on the Stack. Usually, permanents, instants and sorceries are originally cast as spells, where they exist on the stack until they resolve. Once a Creature spell resolves, it becomes a Permanent instead of a Spell. Same for Planeswalkers, Artifacts and Enchantments. Mindbreak Trap can't effect them.