An advocate tries to convince people to do something without forcing something. CEO's doesn't try to convince everyone that working from office is great, they just say that if you don't come to office you are fired. A CEO advocating WFO would be if he was trying to convince other CEO's to also adopt WFO policies. But doing something yourself doesn't make you an advocate.

You're being obnoxiously literal with this. Words typically lead to action but action is the stronger proof. They don't need to be literally "advocating" anything if they're already showing it through action.