On the bigger point, the Constitution grants the Executive the power to select who they want for a SCOTUS appointment, and grants the Senate advice and consent. it doesn't say anything about rationale or whether those nominations meet modern labor law standards. And, in theory, if the nominee the POTUS select doesn't meet seem qualified or meet a high standard, the Senate should be able to exercise a check on that selection, as has been done a number of times in history.
And, again, there is a precedent here that has been set multiple times. I'm just not surprised that only now are we hearing objections to this precedent.... and as buddha suggests, it reeks of partisanship.