I don't think that's true at all.
The base salary for a Justice is ~$270k as of 2021.
FWIW, I don’t think $750k would be too much for a Justice’s salary. It wouldn’t hurt, and would likely pay for itself just through the reduced motivation for corruption.
We shouldn’t have top-level public servants that are struggling financially. We shouldn’t make them ultra wealthy, but paying them enough to live comfortably even if they’re terrible with money and live paycheck to paycheck seems like a reasonable approach.
Literally a joke in The Onion, at https://www.theonion.com/clarence-thomas-promises-to-adopt-c... :
"""I admit to seeing the wisdom in developing some kind of ethical framework for the Supreme Court, so long as Papa gets some sugar,” the senior associate justice said in a prepared statement, emphasizing that he would be willing to submit to a code of conduct that included ignoring special interests and disclosing private trips if there was some serious coinage thrown his way. “It’s reasonable to believe justices serving on the highest court in the land should hold themselves to the highest ethical standards, if only so citizens can have faith in their decision-making process. And if that means so much to lawmakers, they should take whatever donors are giving me every year and double it. Also, in order for me to adhere to some sense of values, Ginni needs to wet her beak.” Thomas suggested he might also support term limits for justices if he was guaranteed a yearly all-expenses-paid trip to the Maldives in retirement."""
I have little money myself, but I have relatives who were high society types and the stuff they talk about is mind-boggling. Massive corruption is just baked in at those levels.
GPT4 summary: "Research suggests that higher government wages can reduce corruption, particularly in poorer countries. However, as a country's income per capita increases, this method becomes less effective, leading to a need for other measures such as improving rule of law, transparency, and better mechanisms for detecting and punishing corruption."