The college forces coalitions to be geographically broad, and the replacement creates failure modes worse than the ones it fixes.
01 Federalism is the point
Claim
The US elects a president of a federation, not a chief executive of an undifferentiated national mass.
Warrant
State-based allocation forces winning coalitions to span regions with different economies. A pure popular vote lets a candidate build a majority from a handful of metropolitan areas.
Impact
Rural and small-state interests lose their only structural leverage in national elections. The magnitude is permanent, not cyclical.
02 Recounts contain themselves
Claim
Under the college, a disputed election is a dispute inside one or two states.
Warrant
Florida 2000 was ugly and it was bounded. A national popular vote makes every precinct in the country relevant to a 50,000-vote margin, with 50 different sets of election law and no federal administrator.
Impact
The probability of a contested national recount is meaningfully higher than a contested single-state one, and the resolution mechanism does not exist.
03 Swing states move
Claim
The battleground map is not fixed, so the neglect argument overstates the permanence.
Warrant
Ohio, Missouri, Virginia, Colorado, Georgia, and Arizona have each swapped categories within twenty years. Parties chase the map because the map moves.
Impact
Prop's harm is real for one cycle and self-correcting across several. That reduces the magnitude enough that the transition costs dominate.