I’ve also heard that the change was made, in part, because the name “Bruce” was commonly used in jokes about gay men at the time; the Wikipedia article on the TV series indicates that both Stan Lee and Lou Ferrigno confirmed that that was part of the rationale, as well.
I think the question is: Do you think Clark Kent is a more serious name than Peter Parker? Do you take Wilson Slade more seriously than Victor Von Doom?
I doubt most comic book fans care. Lets be honest here, isn’t Dr. Doom the coolest super villian name ever?
Hey! Peter Parker was at least the name of a famous admiral in the British Navy.
My personal head-canon is that sometimes the character’s ‘real’ name is part of why they became a hero/villain. If someone grows up with a name like Otto Octavius or Victor Von Doom, it warps them and becomes a self-fulfilling prophecy. It’s much like when a politician named Weiner, Packwood, or Studds inevitably becomes involved in a sex scandal. 
Naita, furryman I think understands my point. If an oceanic hero is named C. King, you might not take him as seriously as opposed to him having a non-pun name. Especially when these characters start getting into some dark themes. He could have been deposed as King of Atlantis and lost his powers and his family or whatever, but he’s still “Sea King.”
Dr. Doom is a cool name for sure, but if his name is Von Doom, then it’s less “DOOM is an awesome name” and more “well, my last name is Doom so let’s just go the lazy way.” Blackagar Boltagon…ugh!
I wager there are plenty of people with dark or questionable sounding names who have changed them to avoid this sort of thing. Others have leaned into them…Dick Hyman, Dick Trickle, etc…
I mean, Richard or any variation thereof would have been fine, too!
I suspect that the vast majority of the kids who read comic books back then (the 1950s and 1960s) didn’t have a problem with taking a superhero or supervillain “seriously” because of a funny/punny name. Your premise seems to be based on looking at goofy comic book names through the eyes of an adult, in an era where superheroes are a major entertainment genre for adults.
(Now, there may have been other reasons for not taking Aquaman seriously… 
)
One of the Spider-Man movies has J. Jonah Jameson (the editor of the Daily Bugle) commenting “Guy named Otto Octavius ends up with eight arms. What were the odds?”.
I don’t take any of them seriously. As a reader, sure, silly names pull things a little towards the silly. But my superhero fare growing up was The Phantom. No silly superpowers, no silly supervillains, no silly names. Just a guy in a blue* costume knocking people out and scaring them with his supposed immortality. And yet I consider my other childhood superhero fare, Adam West’s Batman, only marginally sillier.
Or put more simply, suspension of disbelief when consuming superhero fiction is on a setting where some punny names have zero effect.
*There were some issues when starting to print colored dailies in Scandinavia and he ended up in blue.** The only superhero that is too silly for me is purple The Phantom.
**He also ended up with a wife named Sala due to another mix up.
It’s not that crazy. Lots of nicknames are based off of real-life names. My handle on these boards is based off my real-life name, which I was often teased about. I just embraced it as I got older.
But if I was trying to protect my identity zealously, I would not do that. If my name was Edward Nigma, I wouldn’t commit crimes based around riddles, puzzles, and “enigmas”.
(Though in his defense, he’s insane.)
E. Nigma is a great example! Thanks, Atamasama!
Which reminds me of a name that fits as both a mundane address and a superhero sobriquet:
“I’m Peter, by the way.”
“Doctor Strange.”
“Oh. We’re using our made-up names. Then I am Spider-Man.”
–Avengers: Infinity War
I used to have (but can’t find) a panel from an issue of Superboy from the 1960s. Superboy and Pa Kent are standing at a case in his trophy room containing a love letter from Lana Lang and a lock of lair…um, hair from Lex Luthor. Pa has a thought baloon where he is contemplating the odd coincidence that both of them are "LL"s.
(Also, how weird are those superhero trophy rooms in general and how creepy this example in particular?)
The ones I wanted to mention (E Nygma and Jubal Lee) are covered here or in the earlier link, so how about Kite Man being Charles Brown?
No, it was a section that I saved from an actual digitized Superboy issue I have on my computer.
All apologies; I meant: was it from this issue?
Yep, thats it.
There was some old Action Comic I read recently that involved Superman and some half-ass prophecy involving LL. Dude was going nuts. Stuff like:
“Could it be that ballplayer?? No, his name is just Sam Smith…wait!! BaLLplayer! Great Scott!”
Something like that.
BTW… the kind of wordplay you all are talking about has always been a blind spot for me, unless I actively apply myself to it. I went some ten years before I realized Borg was short for Cyborg.
Please can we also have reaction to Super Ego Alter-Hero puns?