It's really basic stuff, that's why it's a 101 course. However the realities of that kind of course should be remembered and applied to things like "rent control" that acts as an outside influence on where the curves meet, but doesn't actually change the supply or demand directly. Knowledge that would help with assessing the possible intended and unintended results of different laws.
However you miss a points. It's not always or not even often about picking from 2 complex alternatives. It's often a matter of eliminating options that are stupid, illogical, or inconsistent. Doing so often requires basic literacy in the topic involved.
Unfortunately you are right in that disenfranchising a large number of idiots would upend social order even if it was only eliminating those who literally have no idea what is going on.
But how do you know which options are stupid? Because they sound stupid to you? Are you confident enough in your powers of detecting stupid that you would base denying people basic rights on it? What gives you that enormous confidence?
> if it was only eliminating those who literally have no idea what is going on.
The number of people who have an idea what is going on, when we're talking about things like whole US economy, might be surprisingly small. In fact, sometimes I am tempted to think that number is zero. Of course, for me it makes me think maybe we need less government involvement, since a blind giant with a sledgehammer is worse than a blind giant without one, but some people think that means we need to abandon democracy. OK, but unless you are an anarchist, how do you propose to choose the government then? By instituting a series of exams? Chinese tried that, actually. Not sure it worked that spectacularly well. Check it out.
I get a feeling you think you are one of these voters. But are you, indeed? Are you really sure you can predict the impact of the actions in a system as complex as 300 million people inside trillion dollar economy? Before you answer that, remember that many people with advanced degrees tried and failed to predict things about economy, and even more people with advanced degrees are in constant and complete disagreement about what would be effect of that or this policy and what should be done to achieve this or that effect. And "unintended consequences" appears in virtually every article describing the aftermath of any serious government decision. If all those people aren't really able to figure out how things work, are you confident you are?
> should at least be able to pass an ECON101 test
Why ECON101? That course probably provides very basic knowledge (depending on the curriculum) which is next to useless when dealing with enormous and complex systems because it ignores myriad of details. It's ok for a 101 course, but if after taking this course you think that you know enough to make informed decisions about the whole US economy, then this course actually decreased the amount of your actionable knowledge. And yes, voting is making decisions about the whole US economy, ultimately.
> I would really prefer a local, national, geo-political, basic law, and economics (including some light math) test as a pre-requisite for being able to vote
Are you sure you would pass? What if I will be writing the test and make every effort to make you not pass (you don't think politicians would ignore an opportunity as juicy as disenfranchasing a huge number of their opponents' base?)?
You understand also that making decisions for people that can not vote is the reverse of what representative democracy is, and a just cause for rebellion? If any situation justifies violent overthrowing of a government, it is a situation where the government denies participation in vote to a class of citizens which committed no crime, did nothing wrong but failed to satisfy an arbitrary criteria somebody instituted to not let them vote because they didn't like what they might choose. Who would consider such a government a legitimate one? You probably wouldn't, if you were one of the disenfranchised people. But somehow nobody thinks they will fail the test.