So what if Moldova F1 is owned by Moldovans, financed by Moldovans, and only employs Moldovans, but is based in Britain because the factory there is the best available? Are they still British?
Yep. That's quite an extreme example but in this instance where they're from is irrelevant. Where they are is what counts. A British team with Moldovan roots.
How Indian is Force India? I believe they have an Indian licence.
How German are Mercedes-Benz?
Point being, if Alfa Romeo took over Sauber and stayed in Hinwil they'd still be a Swiss team regardless of what racing licence they purchase.