The results are similar irrespective of the system. D&D is a flat system, similar to Cthulhu, and GURPS uses 3d6, the same as Dragon Age. And I’d hardly name Call of Cthulhu an irrelevant system. Many systems are are similar, I just picked three arbitrary ones with different starting probability curves.

If you want the stats in your favourite system, they can be easily calculated:

output d20+5 >= 11 named "D&D 5e linear success distribution, skill +5 vs DC 11"
output 3d6 <= 8 named "GURPS bell curve success distribution, skill 8"

Yes, rolling a 19 in 5E (5%) is more likely than a 5 in GURPS (2.8%), but the actual number rolled doesn't matter; the game only cares if it was a success or not. Yes, the dice roll might be more swingy (as people talk about), but the results are not.

The mechanism design does have an impact on things like critical rate, and also how modifiers affect the system, i.e. does a single modifier step have a small or larger (or one then the other) as your skill level goes up.