Try, if you can, to divorce the filibuster from the current ideological context. Is it really necessary for the workings of our system? I would say no.
We already have plenty of checks and balances in place without it. The House and the Senate may well be held by different parties. Leaving the effects of gerrymandering aside, the House will generally be controlled by urban interests, while the Senate gives disproportionate power to rural populations. Both houses create a check on the executive, and on each other. The presidency checks them both. The judiciary, as long as it remains truly independent and has the support of the American people, is another check. The states have their own powers. Finally, there are a variety of independent bodies, such as the Fed, which play important roles in our system and which cannot be controlled by Congress or the president, Trump’s obnoxious tweets notwithstanding.
I heard a joke once to the effect that it would be impossible to seize power in America because you would have to find it first. The filibuster only makes things worse; it leads to legislative paralysis, and then to dangerous executive overreach to fill the vacuum. And so, there is a strong conceptual case to get rid of it, particularly in a world in which information moves at the speed of light.
The problem, of course, is that it is actually practically impossible to divorce the issue from the present context. It may well be safe and sensible to abolish the filibuster after the largest cohort of reactionaries has left the scene, and millennials are in complete control. Now? No.