Liberals should vote no on Gorsuch but not filibuster. First, imagine that you evaluate nominees along two axes; the first axis is competence (do they have a basically sound mind, are they intelligent, are they respected by their peers, ABA recommendation, etc.) Gorsuch appears to be competent. It is not a thing you could take for granted with Trump; we could have easily gotten a Harriet Miers situation or worse. The second axis is on ideas or philosophy (i.e. their rulings are things I would agree with). The entire shortlist was full of extremely conservative justices, Gorsuch included, anyone Trump would nominate would be conservative, and anyone Republicans would confirm with their majority would be conservative. So this is about what we might have expected, and in a hypothetical reality where some other Republican than Trump had won election, this is what we'd have got.
Given that Gorsuch is competent but not ideologically desireable, why not filibuster? Suppose Gorsuch is confirmed as opposed to Scalia still being alive - what rulings are likely to change? None. 9-0 rulings are still likely to be 9-0. More importantly, which 5-4 rulings under Scalia would change to 5-4 the other way under Gorsuch? Well, if you're a Liberal, you're looking for rulings where the four liberals and Scalia voted against Kennedy, Roberts, Thomas, and Alito. Do these exist? I doubt it. Certainly almost nothing of consequence. In reality, 5-4 rulings are almost invariably either the 4 liberals and Kennedy, the 4 liberals and Roberts, or the four conservatives and Kennedy. Other configurations are exceedingly rare. Conservatives are fighting to defend the balance of power that existed when Scalia was alive. Liberals are fighting to change it. The only way that could be done would be to appoint someone to the left of Kennedy (so 5-4 decisions where Kennedy joined the conservatives become 5-4 decisions with the 4 liberals and Garland or whoever the nominee is). Appointing anyone to the right of Kennedy gets essentially the same results.
Ok, but why not filibuster anyway to leave the current 4-4 state open as long as possible? Well, it depends. If you believe that the Republicans would simply do away with the filibuster any time Democrats try it, then it doesn't matter if they filibuster or not, Gorsuch is still getting through. (There might be emotional value in going down swinging, but the result is the same). If you believe that the Republicans will do away with the filibuster after it is used the first time, but it'll work the first time, then you want to save the filibuster for Trump appointing someone to replace Breyer, RBG, or even Kennedy (all of which would actually change the Supreme Court). If you believe the Republicans won't do away with the filibuster no matter what, I've got a bridge to sell you. So we do no better by filibustering. But if it's really the case they won't end the filibuster, then you trade off having the 4-4 divided and useless court for a little while longer for the fact that it might end up being a 4-3 conservative court by the end of Trump's term assuming there's a cold war of never confirming a nominee again and for the most part the liberal coalition is a lot more vulnerable to age-related dropout than the conservative coalition.
Note that all of the logic laid out so far is just predicated on Republicans exerting maximum will to get what they want. If you re-frame this in the typical good governance setup where what Republicans do depends on public outrage, then I am not sure that you are going to get public outrage about Gorsuch. Trump plainly could have done worse.
Certainly none of this mandates supporting his nomination, speaking approvingly, or not grilling him during questioning. I just simply mean I see little strategic benefit from filibustering. It's hard to think of a circumstance where doing so results in a better outcome.
Normally I'd say "see if you can pick off Susan Collins and Lisa Murkowski" but I doubt it given their willingness to exhibit party discipline during last summer's fiasco. And I think it's more likely you'll lose Joe Manchin and Joe Donnelly. Maybe Heidi Heitkamp too.
