And locusts having four legs is a classification other humans devised.
God would know that locusts do not have four legs, regardless of whether or not the people back then did. God would know that rabbits do not chew their cud, regardless of whether the people back then did. God would know that bats were not "foul" regardless of whether the people back then did -- and God never even tried to set the record straight. If everyone back then had said "locusts have four legs" and God came along and said "locusts have six legs" it would be one of the most revolutionary statements in history. But God didn't do this. Indeed, God apparently is no more knowledgeable than the folks writing about Him.
No, that's an objectively quantifiable phenomenon. Anyome who can count can see that. I don't quarrel with those concerns. But it is silly to expect Iron Age sheep herders to follow modern taxonomic conventions. Might as well expect theme to differentiate between eukaryotes and prokaryotes.