Sources:
https://www.19fortyfive.com/2025/03/the-f-47-fighter-cost-problem-no-one-wants-to-touch/
https://defencesecurityasia.com/en/iran-shahed-drones-gulf-patriot-air-defence-cost-crisis/ (assuming 2 missiles to each drone and the lowest estimate of drone costs)
It’s more likely they’re protecting an aircraft worth hundreds of millions of dollars, but yes, you’re very much right. You can just bleed someone dry with cheap ordinance.