If you think about the range of organisms just here on Earth - from single-celled creatures like bacteria, or below that even with viruses that are just DNA wrapped in proteins, to other single-celled creatures like Amoeba (yes, that's an enormous range still in just the realm of single-celled creatures alone!), to multicellular plants, animals, birbs (haha lolz we know those aren't real!), and finally humans who can literally split and harness the power of the atom - then extrapolate that to the whole Universe in Star Trek, we don't need to think that every super-powerful creature seen is a "Q".

To an amoeba, already every one of the numerous forms of insect life on planet Earth is like a "Q". In that sense then, Q itself was an oddity - not in being a race with that much power, but in choosing to even bother to interact with the lesser forms. After all, we do not do that, to the ones multiple rungs down on the hierarchy below us (or if we do, e.g. yeast, we don't "introduce" ourselves to them, as Q did to humans).

I think it is consistent with Star Trek's philosophy, especially in TOS, that we are not supposed to "know" everything, about the VASTNESS of the large, wide universe it is in:-).