2000 is 11 years after the Soviet empire began to collapse in 1989. A lot of very dirty state-subsided industries in Eastern Europe went offline in the subsequent decade. Maybe that's what we are seeing?
I suppose, but only in the same sense as governments around the world tend to have mechanisms for non-residents and non-citizens to transact business or own property. An Estonian identity certificate doesn't, on its own, allow someone to enter Estonia or live or work there. That still requires citizenship of Estonia, the European Union, or meeting other requirements.