The irony here with what you are referring to, which is what Justice Sotomayor was trying warn about, was the 1935 SCOTUS decision - Humphrey's Executor v. United States
Facts of the case
President Hoover appointed, and the Senate confirmed, Humphrey as a commissioner of the Federal Trade Commission (FTC). In 1933, President Roosevelt asked for Humphrey's resignation since the latter was a conservative and had jurisdiction over many of Roosevelt's New Deal policies. When Humphrey refused to resign, Roosevelt fired him because of his policy positions. However, the FTC Act only allowed a president to remove a commissioner for "inefficiency, neglect of duty, or malfeasance in office." Since Humphrey died shortly after being dismissed, his executor sued to recover Humphrey's lost salary.
Question
Did section 1 of the Federal Trade Commission Act unconstitutionally interfere with the executive power of the President?
Conclusion
The unanimous Court found that the FTC Act was constitutional and that Humphrey's dismissal on policy grounds was unjustified.
(snip)
I.e., this was a ruling AGAINST a DEMOCRAT for firing one of Hoover's appointees "without cause" based on how the FTC law was written.
We are now at a point where the SCOTUS may upend that - in the short term, by STILL supporting the REPUBLICAN.
But the danger is that certain functions MUST BE "independent", otherwise the potential exists for even more rampant rubber-stamping of what many might consider "illegal actions". And if you have your highest court "compromised" by rabid partisanship, then this will probably lead to some states completely ignoring what is going on at the federal level and forming their own "confederacies" (you see that with the medical guidance and states rejecting what the federal guidelines are, and instead relying on their own). I essence, the whole thing starts to fall apart.
The SCOTUS 6 needs to turn this off-course ship around and start reigning 45 in NOW.