It's isn't unzoned. It's zoned commercial. In VA, data centers are considered commercial, so allowed to be built by-right in existing commercial zones. Loudoun Co just updated their local zoning to override this and require re-zoning/approvals. (at least this is my understanding of the situation).

So, you buy a house, and think a small office park or strip mall might get built next door. Instead, it's a 6 story block that looks like the Borg, belches exhaust from on-site generators, and buzzes constantly making you think you have tinnitus or something.