That skew is inconsistent with the constitutional principle of one person, one vote. An elector could well justify a decision to deviate from his or her pledge and vote against Trump based on this more fundamental constitutional ideal.
While they could possibly justify it, they can’t justify it on moral or ethical grounds.
The electors are chosen by their respective States. Since you like Justice Jackson, I’ll use his words from the same Ray v. Blair dissent.
“… they perform a federal function of balloting for President and Vice President…”
So there you have it. The electors are selected and assigned to perform a FEDERAL function. They do NOT perform a national function.
So while an elector is legally free to cast their ballot for whoever they wish to vote for, they are morally and ethically bound to represent the popular vote and laws of the State they are representing, not the national popular vote.
And while the Supreme Court has long held the “one person, one vote” principle as a desired goal, they have never stated that each individual’s vote has to carry exactly equal weight. In fact, they have always couched the one person, one vote concept in terms of “roughly equal”.
As stated by Justice Douglas in Gray v. Sanders, 372 U.S. 368 (1963):
“The concept of “we the people” under the Constitution visualizes no preferred class of voters, but equality among those who meet the basic qualifications. The idea that every voter is equal to every other voter in his State when he casts his ballot in favor of one of several competing candidates underlies many of our decisions.”
The allocation of representatives to the States in the federal legislature as well as the Electoral College — both defined by the Constitution itself, belie the notion of any absolute equality in the one-person, one-vote principle across State lines.