This can't be system agnostic
Every system needs its own different solution for this. How you solve for it in a d20 system (like DnD) is different than how you solve it in a d10 system (like Vampire the Masquerade) or a Fudge system (like Fate), but in general, any system can solve it.
D20
For example: in d20, you can pretty much scale up success/failure infinitely, but your HP and damage dice get way out of hand when talking about really high CRs. So the best way to reduce dice is with damage multipliers and baselines. Consider a 40d6 damage attack. While this attack can theoretically do 40-240 damage, due to the law of averages with that many dice, you will almost never hit outside of the 120-160 range; so, you could dramatically simplify the role by doing something more like 4d10+120 damage. Or if you want a much bigger range 4d6x10 will give you a wide range of damage with very few dice. You can closely estimate just about any DnD damage role with 4 dice or less as long as you use the right added and multiplied damage.
D10
Whitewolf solved the D10 limitations in Aberrant using Mega-Attributes. In D10, you roll a number of d10 equal to your skill+attribute pool for a roll of what is normally 2-12 dice. Normally, for each 7 you roll you get a success point, and the more successes you roll the more powerful your success (or bonus damage in case of attacks). So, to introduce superman like strength they let special Mega-Attributes change how you count up certain rolls with things like lowered minimum targets, and multiple successes on higher rolls such that someone who rolls 6, 8, & 10 with mere mortal attributes, gets 2 success (enough to perform a moderately hard task), someone with a mega attribute might get 6 shifts of success (enough to perform a feat of super human difficulty) on the same roll. This is still a form of addition & multiplication, but applied to how you measure your dice instead of to raw values.
Fudge
Fudge is the hardest common dice system to really do this with IMO because your number of possible outcomes of a roll are already so low. The way this works is you roll 4 special dice with 2 sides that are +1, 2 sides that are -1, and 2 that are blank. Then you add the outcome to a skill value that is typically between 1-4. Fudge is kind of nice because it creates such good bell curves as opposed to d20 where you have linear differences, but it does not scale well because the scope is so small. Sure you can make someone have a skill of 5,6,7... but once you do this, you make all sorts of roles impossible to fail once they drift out of the +/-4 split.
You generally don't want to fix this problem by rolling more fudge dice because that will bias your rolls even harder towards zero. Instead, increasing the power range with fudge requires dice with more sides. I developed a fudge dice roller a few years back that uses d10s with +/-1,2,3 and 4 blank sides that extends rolls to +/- 12 instead of +/- 4 which is far better for having a lot of power classes. Since you are still rolling 4 dice, you don't get a significantly bigger range of common results than normal fudge dice, but it opens up those very rare, 1-in-10,000 strokes of luck which allows a particularly weak opponent to still have some measurable chance of success against a superior foe.
Highly Abstracted Powers
I don't remember what it is called, but I played a Super Hero system once where your powers were abstracted to the point that there was no meaningful difference between one kind of power and another, and tactics were based on creating winning circumstances for your hero more than an actual tit-for-tat combat system. Basically, the game gives you a few dice which each represent a different aspect of the circumstances you are fighting in. I don't remember them exactly, but it was something like 1 die representing how well you fight alone/with other/etc. 1 for how well you face a single/multiple enemies. One for if your environment suits your superpower. Thinks like that. So you try to set up a circumstance that favors your hero, you role all of your circumstances using dice ranging from d4s to d20s and then you pick your highest role as the outcome. This system says absolutly nothing about how you win a roll, only that you do or your don't; so, if a normal human gets a good roll, it might not mean that he punched out the Hulk, it could depending on the circumstances mean that he talked him into calming down, or tricked him into running off a cliff or something like that. This system was good because you did not have to worry about two heroes with incompatible skills fighting each other giving one a ridiculous advantage because how it was won was a matter of storytelling, not dice rolls.
Balancing Powers:
It's not enough to have crazy wide power ranges, you have to ballence them too. Balancing powers in systems that allow very wide skill gaps and/or mega-skills typically fall to the DM's ability to create a diverse range of problems to solve. Put Batman, Superman, and Dr Strange into the same party, and it gets very difficult to imagine an enemy that will challenge the whole group without someone getting OSKed (barring movie magic plot armor). The trick here is not to not make all three guys fight the same fight, but to create scenarios where there are simultaneous problems to solve that no one person can do alone. Batman will never punch out Kalibak, but what he can do is take care of that pesky kryptonite preventing Superman from doing it himself while Dr Strange fights to close off the portal to Apokolips.
Or... you can actually introduce plot armor as a game mechanic. Some TTRPGs have some variation of fate tokens that allow a player to negotiate favorable settings and outcomes, and getting/spending these tokens becomes easier if you are a playing a deeply flawed, non-meta character. So, if you are playing Batman in the above scenario, and Kalibak corners you, you could spend a fate token to declare "I'm just a worthless human, not worth Kalibak's time". If the DM accepts that you've made a reasonable declaration given who the two characters at play are, he would do something like have Kalibak assign one of his weaker minions to deal with you while he turns away to deal with problems more befitting his station... but if superman gets cornered, there is no reasonable plot line in which Kalibak would just write him off; so, Superman's player could not spend a fate chip to break agro.