Nice Guy replied to my initial response in his "comments" section. Here's today's contribution from me:
The reason to do away with the filibuster is that it's anti-democratic. Not every part of a modern liberal democracy is supposed to be entirely democratic, but the legislature is, and the filibuster, whether used for good or bad (and, historically speaking, it's almost always for bad), is a cancer on that scheme.
Your argument against the tyranny of the majority is fundamentally (and profoundly) conservative--it's the very reason great effort was originally expended, in the creation of the constitution, to minimize democratic influence. The powdered-wig set was terrified that ordinary joes--flush with the foolish notion that, because they were the ones who fought and died to create the country, it was theirs--would take up arms and storm the country clubs, demanding a fair shake. The views of the powdered wigs on this point were fundamentally at odds with both the temperament of the times and of the American culture and character, which were products of that temperament. We never accepted their views, and our history is one of correcting them. We are a liberal democracy, even more so culturally than is reflected in our governing institutions.
That's certainly not to say the tyranny of the majority is something toward which I'm indifferent. When it comes to the general public, the ignorance, the educational deficiencies, the fact that it can and often is duped, that it can react like a frightened herd when faced with crisis--these are all undeniable, and all undeniably matters of concern. Leaving the general direction of the country to the ballot box, as I suggested earlier, could and would lead to some appalling outcomes. I don't even look upon that as a proposition--I accept it as a fact.
Here's the thing, though: I don't think there's any reason to believe those outcomes are any worse than the appalling outcomes we get now. We have most of our history to show for that. Filibuster abuse--if one accepts that any filibuster is not an abuse--is a relatively recent phenomenon. The incredible degree of abuse we see today is, in fact, only 3 years old, with it having become a problem of note less than two decades ago. Launching a filibuster used to be widely considered the legislative equivalent of child molestation. It was practically never done, except in the service of causes like beating back civil rights, and the U.S. kept chugging along anyway (the process was formalized way back in 1917, though, in practice, there had been filibusters going back to the 1830s).
It should also be said, though, that allowing one's position on this matter to be driven by concerns for the outcomes we may get should the filibuster be ended is completely inappropriate. That isn't to say we shouldn't have those concerns--we certainly should--but allowing that to drive your ultimate position on the question is to adopt a Machiavellian ends-justify-the-means perspective that is entirely inconsistent with a democracy. One either believes in democracy or one doesn't. If you believe in it, you have to take the good with the bad.
I do believe in democracy. In fact, I've always been one agitating for making things even more democratic. I'm all for proportional representation in congress. I'd completely eliminate the electoral college. If I had my druthers, I'd probably even do away with the Senate itself. I'm not as settled on that one as on the others, but over the years, I keep asking myself if we really need a House of Lords. At the very least, some neutering of Senate power seems appropriate. Consider that, at present population dispersal, just over 5.6% of the U.S. population, residing in the smallest states (which contain 11% of the total U.S. population), can theoretically elect a sufficient number of Senators (41) to filibuster anything everyone else wants to do. It doesn't work out that way in practice,[*] but that's obviously an intolerable situation for anyone with any real concern for democracy at all, and depending on the forbearance of reptiles is not a sound means of addressing it.
You ask, "Are Supreme Court issues, 'matters for the ballot box?' If you say 'yes' you sound a lot like a Conservative. If you say 'No' then you've undermined a good chunk of your argument." By "Supreme Court issues," I assume you mean things like matters relating to civil liberties. Of course those aren't subject to being eliminated by a majority. Protection of minority rights is an integral feature of a modern liberal democracy, not, as so many conservatives would have it, a deviation from it. My right to free speech can't be legislated away. Well, actually, it can, but that's why we have the courts, to smack down that sort of nonsense. That isn't why we have the filibuster. The filibuster, like the Senate itself, exists to put a stop to change, to short-circuit those durned libruls who are always tryin' ta' make things better fer folks. It's a practice, just as the Senate is an institution, designed to prop up the status quo. The sentiment behind it is consistent with a part of the sentiment that led those powdered wigs to create the Senate in the first place, though the filibuster itself is arguably unconstitutional, by the very scheme those powdered wigs established. My failure to submit fundamental rights to a majority rule does nothing at all to undermine my argument, much less "a good chunk" of it. It is, rather, a matter of apples and oranges.
As I said before, if one believes in democracy, one has to take the good with the bad. I don't think the bad would be as bad as you seem to think. I don't think people are as stupid as you seem to think, either--most of the time, they're either with the liberals or come around to the liberals' point of view over time, and if we accept that as "stupid," we're sort of stupid, too! Maybe we shouldn't rule that out! I don't think we should be looking at possible outcomes as the guide in this matter.
The constitution allows the Senate to make its own rules, but it provides for a majority vote to pass legislation. The filibuster, as it's presently constituted, makes a supermajority necessary. That's the sort of tinkering with the original design that probably should require a constitutional amendment. Calling out--and defeating--the Republicans who have brought us to this place is a good idea, a good use of democracy, but it doesn't fix the institutional problem. As I see it, one can either stand against the filibuster or accept that the constitution got it wrong and that we really should have to have a supermajority to do anything. I don't see much wiggle-room between the two.
[*] The actual numbers still make the point, if much less dramatically--at present, Democratic Senators represent 74.9% of the population, while Republican Senators represent 48.7% of the population (there being overlap between states that have mixed Senate delegations). The minority is still running everything.