Will every Xbox 360 game be added to the Xbox One compatibility chart?

While no one can say for sure I would say probably not.

It's down to the developers/publishers whether their games are made backwards compatible so it's highly unlikely they would spend the time & effort making less popular games backwards compatible.

If you find a game I say buy it anyway,you can always pick up a cheap 360 in the future.

There is also the number of arcade games that have been delisted from the marketplace and the games that have had their servers shut down. The possibility of those games being made backward compatible when not every gamer can play them to their fullest is
essentially zero.

Not all Original Xbox games is able to be played on Xbox 360.

Games needs to be added to the backward compatible library to be able to be played on the 360 or the One. Seeing as they have stopped bringing games to backward compatibility, team has been reassigned to work on Project Scarlett, we might see more games
added in the future.

Microsoft is constantly adding games to backwards compatibility. Your best method of getting a game backwards compat is social media with the developer of said game. Games bought on the Xbox One aren't compatible with the Xbox 360 I'm afraid. You'll need
an xbox one to play it.

Hope that helps.

I hope the new xbox could play every game released. So many xbox and xboox 360 games weren't added to backwards compatibility due to licensing and all that. But more than likely it will be the current list now with some more titles added later.