Well then you're taking the opposite view. Your argument wouldn't be to stop data centers due to water use, it would be to secure water use for clean drinking water first before other uses are considered.

That angle opens the argument to concerns from various fronts, including data center use but also concerning things like agricultural use if that's a concern for you.

The drinking water concern also would hinge on having to define "clean drinking water." Humans have made do with drinking from streams, rivers, and ground water for most of human history. Today into he west at least we largely drink recycled waste water treated with bleach and various other chemicals. Drinkable yes, but I'd personally rather drink some rain water than bleach water.