Golden Age Superman or Kal-L is VERY much a different character than any other mainstream versions of Superman. I mean yes, every version of Superman is different from the last but Kal-L stands out the most. The source of his powers are different, how his powers WORK are different, he doesn't work for the Daily Planet but the Daily Star, his adoptive parents are John and Mary Kent instead instead of Johnathan and Martha Kent, and he was generally more hands on when dealing with criminals. He TERRORIZED them with his strength and speed, to the point they broke down and WANTED to go to jail just to get away from him. He also didn't exactly care if he killed criminals. He might not have always MEANT to kill them, but the way he threw them around and hit them you could pretty much say that yeah they were dead afterward.

The Kryptonians from the Earth-Two universe did not rely on the absorption of yellow solar energy to fuel their powers, they relied on their own internally generated bio-energy. All Kryptonians of the Earth-Two dimension had powers inherent to their own evolution and physiology which included being able to lift numerous tons, as well as the ability to leap thousands of feet into the air, sub/near sonic speed movement and high end endurance, unlike other-dimensional Kryptonians who need yellow sunlight to accomplish the same feats.

Obviously not strong enough to survive a planet blowing up around them, but still.

Now I know a Superman appears in Earth 2, but on the DC wiki he's listed as Kal-El, not Kal-L. I ask because I wonder, did DC LOSE the rights to the ORIGINAL Superman?

And, Kal L could easily survive a planetary explosion. He was only at weaker levels until 1942, to which they amplified him to Silver Age levels. He was a match for the SA Superman. He was only the ''leaping Superman'' for a short while.

The new Earth 2 Superman is very much the New-52 version, they just dropped the Kal L name and instead opted for Kal El, they also radically changed his personality so that pre-Brutaal personality was basically Pre-Flashpoint Superman.

Also, Kal L did need Solar energy, it was retconned to be that way.