One specific objective was to validate the previously highlighted underlying reasons for the observed selectivity drop at high pressure in certain highly selective materials at low pressure. Previous studies found that high diversity of pore sizes and channel sizes that favor adsorbate reorganizations could be at the origin of this phenomenon. Through the application of interpretability tools, quantitative factors explaining the conservation or decrease in selectivity for highly selective materials are identified. Depending on energy averaging at 900 K, statistical characterizations of energy or pore size distributions, and differences in occupiable volumes, a structure could exhibit either a selectivity similar to the infinite dilution case or a substantially lower selectivity at higher pressure. The XGBoost model employed in this study utilizes a complex ensemble of decision trees to capture the quantitative rules that can be extracted from the model and used to establish heuristics supporting the intuition about Xe/Kr selectivity in MOF structures.