Makes perfect sense to me.
When Crisis Of Infinite Earths began, Pre-Crises Earth 1 and Earth 2 were split off into Earth 1985 and Earth 1938 respectively. This preserved previous eras of Superman. Just like when Earth 2 was split off from Earth 1 when Barry Allen discovered the Speed Force.
Then Earths 1, 2, 4, S and X (Quality) were merged. A new era for Superman - the Grimdark hot mess era. (Out of curiosity, when did this era end and a new begin for Kal?)