I personally believe if his appointed justices were directly involved in the SC's refusal to hear cases regarding the 2020 Presidential election, PDJT wouldn't hesitate to call them out.

He's certainly fulminated about "the courts" failing to do their job and their duty, but if he's been hesitant to specifically criticize Gorsuch, Kavanaugh, or ACB for their dereliction, I think it makes it more clear that Trump's unhappiness with "the courts" for declining to get involved is a bit of an act; he would know better than anybody if/that the SC declined to hear the cases because these will ultimately (and shortly) be heard by, and decided upon by, military tribunals.