If you are truly a Superman fan, then you'll know this,,,

Gee You can Quote Kill Bill... Good for You... would you like a cookie.

having heard understanding or Believing this Does not make one a fan nor is being a Fan mean you were exposed to the statement and the idea within.

and really Both 'Clark' and 'Superman' are Masks to a degree... Just like the You who sits in a Cubicle surfing IMDB, making 'That's what she said' Jokes to your Boss and bringing cookies to the Pot luck is not the Same You that scrap books, uses Pintrest and goes antiquing with your Grandma

we all assume roles based on the situations we are in: lets face it a dork in a suit catches a helicopter you'd wet yourself. A God in spandex does it and the weird is too far off the charts to worry
-- and it doesn't matter how strong you are you can't make a habit of wearing spandex and Capes in the office, no matter how casual 'Casual Friday" is.

his powers may always be ON but he was still raised as Clark Kent (adopted) son of Kansas farmers, he attended High School and either because he couldn't play football hid in his books, or because his powers were not yet 100% he was a Normal kid who excelled at sports
-- and being the one kid who literally Cannot be hurt among a species where adolescence is typically full of risky behavior and stupid decisions only serves to Confirm any opinions of Human Fragility and makes it some thing to respect and protect NOT Critique....

So whether Tarantino or the writers really believes this, or were writing it in the Voice of Bill, who being an Evil Douche Canoe, is not exactly a great philosopher with an opinions to be adopted

They're both masks. Clark Kent is an intelligent, well-spoken but frail intellectual. Superman (in his earliest incarnations, at least,) was a squinty-eyed, barely-speaking brawler. As Clark he hid how strong he really was and as Superman he hid how smart he was.

--
Hulk want hug kitties
But they so easy to squish
Hulk live in cruel world

That was Superman, before the eighties reboot.

He was born as Kal-El, raised as Clark Kent, and became Superman last.

He created the Superman persona, at heart he's Clark Kent. (And throws in a bit of clumsiness because glasses aren't much of a disguise by themselves)

Yes, he is born Kal-El but he isn't 'Superman' on his native planet or anywhere without a Red Sun to give him his extraordinary powers. His chosen persona was created to distance himself from that of his Superhero self, rather than his depiction of the human race. Afterall, he knows and dmires many powerful and strong characters in his world.

Batman isn't actually Bruce Wayne, Bruce Wayne is the mask for Batman, something he would shed if he could get away with it.

Spiderman really is peter parker, that's his thing - always struggling with balancing his personal life with the mask where the mask always tends to mess up his personal life.

Superman was born Kal of house El on Krypton, when he arrived on earth he became Clark Kent before taking up the persona of Superman. And Clark isn't weak, he's crafty and cautious, but he is not the way Superman sees humanity, he's what he think people will see as an improbable disguise for Superman, I mean who with all that power would spend his time pretending to be an unappreciated reporter?

Light travels faster than sound,
that's why people seem bright,
until you hear them.

Kal-El wasn't born wearing the suit, you know. He was a refugee when Krypton went kaboom, and a baby at that. What did he know of his home world, or what he would accomplish on Earth? Depending on the writer of course, probably not a whole heck of a lot. Then he was found and raised by the Kents, knowing only that he was "different" for years before he discovered the truth in one way or another.

It's like any human child growing up with an adoptive family. Even when taken in very young, as Clark was, they often feel a little "out of place" and want to know why. However, once their origins are learned, does that mean that they're no longer the same individual they were five minutes before? Of course not. As noted in "Dogma" (copied/pasted from Wikiquote):

Bethany: [miserable] Everything I am is a lie?
Metatron: No, no, no! Knowing what you now know doesn't make you any less who you 'were'. You are Bethany Sloane — no one can take that away from you, not even God. All this means is a new definition of that identity. Be who you've always been. Just be this as well... from time to time.

*shrugs* Besides, even super-powered aliens have to stop and rest occasionally. You know, recharge with friends and family, or a good book... heck, maybe even a bit of sleep now and then. It'd be impossible not to go completely mad otherwise.

Personally, I think they did the balance pretty well here. Here's how I break down the different facets of his character in the series:

Farm Clark ~ Most often seen with his parents and later Lois, or just on "down time" by himself. A lack of glasses and a casual use of his powers are frequent at such moments. Seems the most "whole," if you will, and definitely the most at ease.

Glasses Clark ~ Mostly in Metropolis, particularly around the Planet. Bit clumsy and awkward, often has to dash off for patently flimsy reasons, especially in the early episodes. Always on guard and unsure who to fully trust, but generally first in line to help whenever necessary.

Superman ~ Kind of obvious here, naturally. Has an interesting habit of crossing his arms and engaging in stare-downs with bad guys, though. This tends to have varying effects, depending on the level of "bad" he's facing.

Kal-El ~ Briefly during the "New Krypton" arc. We see a lot of the "Superman" side here, but he's clearly highly uncomfortable with his new role as Kryptonian royalty. Would much rather be on Earth, but feels a certain obligation to what remains of his people (that aren't, you know, power-mad psychotics)