What factor would exclude overharvesting as the cause of the decline in edible fungi species?

The decline in edible fungi species being linked to a parallel decline in non-edible species suggests that the issue is not specific to overharvesting. Overharvesting typically impacts only the targeted populations, while a simultaneous decline in non-edible fungi may indicate broader environmental changes or ecological factors affecting all fungi. This correlation points to underlying issues such as habitat loss, disease, climate change, or pollution rather than specific human harvesting practices. Thus, the presence of a parallel decline in non-edible species effectively excludes overharvesting as the sole cause for the decline in edible fungi, highlighting the complexity of ecosystems where multiple factors can influence species populations.