NFL site has a good breakdown of what opting out means and who has so far:
https://www.nfl.com/news/list-of-nfl...of-2020-season
Interesting that it's seen as an advance on salary, so presumably they lose the money from next years salary when they return. Be curious to know how that works out if they are cut etc. prior to next season. Will the NFL/team waive the money if there are no owed earnings to deduct it from?