(DTC) Datacentres take electricity and turn it into low grade heat e.g 60c water. Put them anywhere where you've either got excess (cheap) energy or where you can use the heat. Either is fine, both is great, but neither is both bad and current standard practice.

It's perfectly possible to put small data centres in city centres and pipe the heat around town, they take up very very little space and if you're consuming the heat, you don't need the noisy cooling towers (Ok maybe a little in summer).

Similarly if you stick your datacentre right next to a big nuclear power plant, nobody is even going to notice let alone care.

Resistive heating is a tremendously inefficient way to generate heat. Sometimes it's worth it if you get something useful in exchange (such as full spectrum light in the winter). But it's not all upsides.

Heat pumps are magic. They're something like 300% efficient. Each watt generates 3 watts of useful heat.