Whilst I can see why that might be a publicity problem for Disney, it isn't like he was doing anything untoward in his workplace.
HR violations take a backseat to publicity. It ought to be the other way around, but that is how it is in this business.
Did they fire Johnny Depp and shut down an entire franchise only because they thought they were doing justice by Amber Herd? Heck no. Otherwise they would have let the trial pan out before they disavowed the guy. For the same reason they jettisoned James Gunn, because of the optics of his pre-Disney Troma-era tweets. And, for the same reason, they got rid of Johnathan Majors.
I feel there was something about DeMayo that would be more bad publicity (after a string of bad publicity) for Disney, if it came out. An OnlyFans seems about right.
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now my soapbox:
While HR violations take a backseat to publicity; publicity, in turn, takes a backseat to internal politics. John Lasseter, who was supposedly fired for "hugging" too much, was a fatal loss for PIXAR. With the acquisition by Disney, he got caught up in a move to displace key staff with actual diversity hires. On the meeting where his firing was discussed it wasn't two seconds before someone said, "Now, can we get a woman to replace him?" Lasseter was eventually replaced by Jennifer Michelle Lee as Chief Creative Officer.
John Lasseter had given us the classics (Monster's Inc, The Incredibles, Ratatouillie, WALL-E, Up, Frozen, Inside Out, Moana, Coco ... and basically all the films that made me cry). The last film to have any essence of Lasseter was Encanto. The first film with Jennifer Michelle Lee completely at the helm was Strange World then Wish...
All because of internal politics.