It's ironic when data center operators, who I'd expect to be experts on calculating complex cost/benefit scenarios, check for & arrange what's needed, sidestep better solutions because there's a bunch of requirements attached.

Reads to me as going for a quick & dirty fix.

I'm not an expert in the US grid, but where I am, the grid moves at a different pace.

It also has a bunch of constraints that are not that appealing. For example there is a strict supply limit. You can't just attach 4x6MW connections in a few weeks. More over, that kind of cable is £900 a meter, at the least. Its also oil filled and needs a bunch of other infra to keep it cold.

Then, the lead time for transformers is also quite high. I'm not sure about the switch gear and meters though.

Once you have all that, you need to make sure your local spur of the grid has enough capacity to provide what you need.

Then you can bid for a connection. THe further away you are from the grid the more it costs.

From what I've read, it's mostly about time.

Attaching to the grid, at the powers desired, in the locations desired involves years of waiting beyond construction. Onsite genetation can be built within the overall construction timeline.

Maybe poor site selection, but I'm sure there's a cost optimization there. And my understanding is that there's not a whole lot of excess grid capacity around the country at the moment. Utilities are spending a lot of resources on changing the mix of generation and wildfire mitigation and don't have a lot of resources for adding generation capacity beyond what is immediately needed or increasing interconnection capacity.

This is different than the data center boom in the .com era; site selection was different, the grid situation was different, and the data centers being built were smaller loads.