This workaround could help Steam users get into the game.

Following today's Season 6: Dark Creations update for Battlefield 2042, most Steam players have run into a bit of a snag. When attempting to launch Battlefield 2042, Steam will attempt a "Validation" step for the game instead of launching the game. Once completed, the game will still fail to launch and kick off another "Validation" step.

Dialogue box asking the user if they want to clear the cache for the EA app to fix a Battlefield issue.

It seems that a workaround to this issue lies not within Steam itself, but in the EA app. The Battlefield Comms Twitter account provided some quick and easy steps on how you may be able to fix this issue.
  1. Close Steam
  2. Open the EA App
  3. Click the "Hamburger" menu icon on the top left of the EA app
  4. Highlight "Help" from the Hamburger menu
  5. Click "App Recovery" under Help
  6. Click "Clear Cache" on the popup that shows
  7. The EA app will close and may restart. You may need to log back in to the EA app
  8. Start up Steam
  9. Click to play Battlefield 2042
These are the exact steps that I took to fix the issue and it worked for me. Your milage may vary, of course.