It's funny, when this topic comes up, the people that are juggling multiple jobs are usually stuck in this weird place where they want to convince people it's true but at the same time not draw too much attention to it (for obvious reasons).
And a lot of this comes from people who are far less wordly than they think they are. Like there are people that genuinely believe that no one in security makes more than $200k except CISOs.
I understand it's entirely possible to juggle two remote jobs, I just don't think it's nearly as common as people claim or think, which is why it's an easy lie to make. It's got nothing to do with the total salaries involved, and everything to do with the exceedingly rare nature of the claim.