Why is moonlighting unethical? Let’s keep legality aside for a minute although it is not illegal.
Your senior leaders are directors at multiple companies.
CEO of startups like Lenskart, shadi etc are sitting on TV for personal investments which they will make money of and spending hours in shooting. Those same CEOs layoff as per their whims and fancies.
But when a lowly employee with a meagre salary tries to increase his/her earning potential, this crab mentality kicks in and it becomes unethical.
A person can be too good to handle both(or more) jobs superbly. However, if there are performance issues, you deal with that as an employer. It’s not like people working on a single job don’t underperform.
Also, there are 24 hours in a day and I am “supposed “ to work for 8 hours. Mathematically, a person can work 3 jobs in a day (and try to sleep at work).
We all rooted for Will Smith in the “Pursuit of Happiness “.
Toodles!