I assumed most domestic sales were going to closed frontier models, through some mechanism or another (direct ownership, cloud resale, whole-gpu or whole-dc lease, etc). Got any numbers?

Ultimately if you have a GPU that can fit X parameter model at Y raw tokens per second, you want the smartest weights. If the frontier closed model is Z% smarter or “more valuable” you would be willing to pay up to Z% margin for the right to use it. Hence whether you are running open or closed model depends on pricing strategy of the frontier labs, also whether the frontier labs are able to diffuse their own models better than open labs can.