To be clear I don't think everyone doubting their supposed omnipotence is saying it's because of technology. That's unnecessarily reductive. There are just general doubts that Q has always told the truth about his peoples' power. It's due not only to Quinn (or even Voyager at large), but many small indicators (Amanda, Guinan, the persistence of other similar races that do not make such claims but possess demonstrably similar power), as well as the fact that we have only one Q's word.
And that one Q is possessed of a rather acerbic, mischievous and mercurial personality.
Remember Nightdiamond, the Cardassians are the Alpha Quadrant's most magnificent civilization...according to the Cardassians. Of course, because they're closer to humanity's level, we can clearly see that they are not. The Q ask us to trust, on faith alone, that they are basically gods and the only proof they offer us is a bunch of (admittedly frighteningly powerful) parlor tricks and the occasional wonder.
As you may know, omnipotence is considered by most non-religious folks to be an immense paradox: if an omnipotent being can create a stone too heavy for it to lift, how can it be omnipotent; but if it cannot....and so on. The Q have already shown themselves vulnerable to death. Whether it is in their own nature or not is beside the point. If an omnipotent, omnipresent entity can be made to cease being omnipotent, then was it really ever omnipotent in the first place?
That made me wonder.....What about having an IQ that allows them to defy the paradox? Who knows---create a copy of one's self that cannot lift a rock, except the original can lift the rock because he created the rock and the copy?
By what laws of logic does the Continuum operate? Simply saying that it's beyond our "puny" minds is a cop-out.
In EAF when Troi sensed Q, she said that it felt like it was beyond what we would call a life form. The idea implied was that they were so advanced they were way beyond the simple measurement of alive and conscious.
We don't automatically think, simply because we can't explain how the Prophets work, that they're omnipotent. Why does Q get the benefit of the doubt? His boyish charm?
Super powerful? Obviously. Omnipotent? Doubtful. And to be honest I also doubt anyone on the Enterprise-D or Voyager ever truly believed this either
True-- there's no need to kneel down in awe of Q when they may be simply operating in ways we yet don't understand.But what makes the Q different from the Prophets for some fans, is maybe that Q was shown doing things almost unheard--=even for an entity -- at a whim.
Shrinking Voyager into the size of trinket, transporting it to earth, possibly in the past, and hanging it on a Christmas tree, was one of the wildest things. The Prophets, The Dowd, Organians can do interesting things, but this way off the charts in power displaying.
Do we think the other entites can do things like that in real time space? So that creates the question, if the Q could manipulate matter and space like that, what the hell can't
Just for laughs, Q turned Beverly Crusher into a dog while she was nagging him--and she had no idea.
From time to time, in some rare cases, even Picard was shown being awe of Q, but true, basically he was the main one to call Q a sham.
Thinking that destroying the human form a Q inhabits even slightly inconveniences a Q is naive in the extreme.
Are the Q arrogant, etc? O, yes.
And they have the power to back their arrogance up - and more. If Picard manages to actually annoy Q as opposed to merely amusing him, Q may just decide to bitch slap Picard by removing the human species from existence with a snap of his fingers. He even did it once, in TNG: All good things.
It is interesting that in EAF, Q freezes a security guard when he reached for his phaser and then told Picard something like, "knowing humans as you do, Captain would you be so captured helpless by them?"
Obviously the guard would not have been able to hurt him, yet Q's reaction was strange-- they always throw in strange scenes like that to make you wonder.