well, they did have to change the definition this year to cover the situation. https://www.washingtonpost.com/documents/642decc6-c0f7-4487-bcea-64efc7ab3346.pdf?itid=lk_inline_manual_9 this article came out a day before the propublica piece and was written by Pritzker Law prof who writes the textbook on judicial ethics:

Under the old Judicial Conference rule, issued pursuant to the federal Ethics in Government Act, “judicial officers” were required to report the receipt of gifts worth over $415, with a broad exception for “personal hospitality.” The term “personal” had apparently been interpreted to mean something like “extended by an individual” rather than by a business or corporation, thus allowing the undisclosed acceptance of resort vacations and private jet travel, so long as the invitations were made by acquaintances, even if some other entity was underwriting the expense.

At Whitehouse’s urging, the Judicial Conference Committee on Financial Disclosures has announced a revised definition of personal hospitality, for which “the reporting exemption does not include . . . gifts paid for by any individual or entity other than the individual providing the hospitality, or for which the individual providing the hospitality receives reimbursement or a tax deduction.” In other words, no more private gifts by proxy. https://thehill.com/opinion/judiciary/3934664-will-the-supreme-court-justices-comply-with-new-rules-on-gift-disclosure/

I'd like to know where "personal" was interpreted but even without it, the changing of the regs militates towards it being an existing loophole, and against your and slate's interpretation. Not a thomas defender I just hate bad arguments and it seems all there are is bad arguments about this.