"Because money" is oversimplifying it.
No, it's not. I'm not doing the simplification; the 90% is. While I do get that you're trying to imply that polling is flawed, which it certainly can be, when the numbers get over 90% your denial has crossed well into delusion.
No, it really is that simple. Polls (and those polled) can manipulate results 5-10 points one way or another, sure. You mentioned the last election, where Clinton polled slightly ahead and then Trump won key states by the slimmest of margins. It mattered precisely because the election was divisive. When the numbers are round 40%, 45%, 50%, 55%, it matters. Who were polled, and when, who votes among them, where they live, what percentage is lying, it all matters. Both parties spend billions each year to track a 43%, determine if it's really a 40% or a 47%, and how to get it up to 51%. If gun control was a 50-50 split, or even a 55-45, you'd have a point.
An issue that polls over 90%, even once, is something else. The electoral college does not have the ability to overturn a 90% popular mandate; it has never done it in its history. Voter suppression doesn't. Gerrymandering doesn't (voters aren't gerrymandered over gun control; they're gerrymandered around race). Literally nothing does. It blows every single argument you have out of the water unless you throw reality itself out the window, which is what you're doing. Issues polling over 90% in one direction are considered rare, uncontroversial and truly bipartisan, because you can't get there with one party alone. The debate, then, is entirely in the realm of hysterical propaganda. Political games are all about creating wedge issues and then bargaining with factions to combine the 35% party loyalists you have with whatever gets you to 50% plus one. That's the kind of crap you're talking about. 90% is a number that transcends that nonsense. 90% is not a wedge issue; it's literally a third rail, if it mattered. There is
no way you slice 90% to get the piece you're going for to under 50%, and hell, even at a hair under 50% that's enough of a chunk of voters to give legislators pause, if you think
anything gives Congress pause. Which is my point -- the only way Congress could blatantly and repeatedly defy an issue supported by 90% of the public is if the numbers don't matter at all.
Which means only one thing: that Americans don't care. Not even voters, which are a bigger percentage of the population than you think, if you're trying to wish away 90% into utter irrelevance. No, it's just that gun control
isn't the divisive wedge issue Congress makes it out to be, because if voters actually cared, then Congress would be on the right side of the issue. Yet no matter how many massacres there are, Congress is never punished for selling their voters out to the NRA, so they keep doing it. The NRA's power is an illusion sustained by apathy, for all the thoughts and prayers offered each time this happens.