I think it's a natural reaction to the "our AI systems are really dangerous and might kill you all and will definitely take your jobs" messages that have been coming out of the AI labs for the past few years.

They've dialed them back a bit now, but way too late. That message has sunk in.

Campaigning to prevent data centers from being built is the most actionable thing a US citizen can do, because it's a local issue (and hence something they can influence), plus they can use arguments about noise and power prices and water pollution to help make the case.

(I think most of those arguments don't stand up to scrutiny - as light industry goes data centers are pretty minor, would you prefer a concrete plant in your back yard? But I don't think the arguments are the point for a lot of people. It's about having a way to oppose AI generally.)