Until you prove it in practice, i’m Guessing that they have not.

you have 5 starters that are elite players, there isn't quite the need for any bench play more than token appearances if you do not think they are ready. The last thing you want to do is to throw them into situations where they might be overwhelmed and it shakes their confidence. There will be plenty of time for development in many other games this year. Yesterday probably wasn't the game for them to learn much.