Could a different US Secretary of the Navy in 1912 lead Pennsylvania and later standards to carry 16-inch guns?
Short answerPossibly, if Congress funded it; Pennsylvania might carry eight 16-inch guns and trigger a larger British response.
NotesThe US Navy was already interested in heavier guns, so a different civilian decision before funding and construction could plausibly change the class. The likely arrangement would replace four triple 14-inch turrets with four twin 16-inch mountings. Announcing that program while the Queen Elizabeth class was being finalized would pressure Britain to accelerate its own 16.5-inch work rather than remain with the 15-inch/42. The answer keeps Congress as the essential constraint because technical interest alone did not authorize the ships.