Around 7 people the US get the plague each year. Yes that’s low, but it’s low specially because measures actively keeping it low.
Which means understanding and maintaining these systems is still valuable as even if millions aren’t actively dying, that can change,
Whereas tens of thousands contract Lyme, often in life altering infections. Lyme is a big deal. But yes, I agree, we can both aim to reduce new disease without letting old vectors for disease back in.