I do think a lot of people are projecting their societal and marriage expectations onto Jensen. They're expecting that he should follow the same set of standards they follow with their partner. Yes, monogamy is the societal norm - but it is not a requirement of a relationship. And, it is certainly not a requirement of a relationship that you're not a participant in.

In my eyes, this all comes down to the perception that someone is able to be compromised by non-monogamy. Jensen came out, apologized to his wife, and (at least publicly) communicated that he broke the expectations and boundaries of their relationship. This clearly communicated that a secret relationship compromises his position. And, should there be more secret relationships they'd continue to be used as leverage.

Musk isn't subject to this leverage because it's pretty clear that his relationships are not built on traditional definitions. Non-monogamy is either a clearly defined boundary in his relationship or simply not something that concerns him as leverage.