Are you just talking hypotheticals, or is there actual evidence of corruption? Since federal judges don't have to run for reelection or anything, it sounds like you're implying direct bribery
It's not often that you specifically state "I will now proceed to give you these monies so that I may receive the following services from you in return". You "donate" to campaigns, you go to fundraisers, with the understanding that once they are elected you will come knocking to ask for a "small favour" in return...
Federal judges don't have campaigns or fundraisers. Unless the judge took a bribe, or retires and becomes VP of Whatever at Palantir, crying "corruption" just seems like being cynical for the sake of being cynical.