But that's just the problem. Doomsday is just brute force. The idea that Superman would be afraid of something that can only punch him is an affront to his character. Superman isn't just a pile of muscle, he's got a genius intellect and a creative approach to problem-solving. A literally mindless punching machine shouldn't pose a significant threat to him at all. He should be able to think of a creative way to neutralize the threat, rather than just trying to punch back. Doomsday is just so, so much less than Superman that it was an insult to pass him off as Superman's ultimate nemesis.
The one thing about Doomsday that would scare Superman is that Doomsday would relentlessly destroy any civilians who got in his way. That's what Superman fears -- not his own death, but his failure to protect others. But it undermines that when Doomsday is monomaniacally targeting Superman himself and everyone else is just collateral damage.
Doomsday passed off as Superman's ultimate nemesis is an insult to Superman himself - oh, I concur with that. I mean, Supes already has a nemesis, and it's this guy named Lex Luthor. Doomsday is not Bane - and with that, I mean his Comic-Book-Counterpart, the one, who is brawn
and brain, the one, who broke Bruces back. Here, I can get, why people didn't like the Bane in B&R, by the way. That Bane was nothing more than DCs Version of the Hulk, working with Poison Ivy.
But Doomsday is more of a monothematical creature - not even a real villain, but just a being, that gets pleasure out of killing and destroying. The only reason
why Doomsday is seen as Supes ultimate villain, is because it's the beast, that killed Superman off. And if one would just want to see "Doomsday done right", then I suggest, just to film "The Death of Superman" - it has been done as cartoon, now do the real-life-version of exactly that. Don't put it at the End of BVS, just film "The Death of Superman" - it's a no-brainer to create. You don't even need people to draw the storyboard, 'cause it's all in the comics.
If Doomsday wouldn't have killed of Superman in the comics, no one would even talk about this character. He was a plot-device - a bird-smashing, houses-punching, Superman-killing plot device.