Alldoraafi

whoops, I meant "StateFlags" sorry for the typo The "DlcDownloads" didn't exist in my other games' .acf files so I deleted it from my FO4 one, I think it's a list of DLCs to be downloaded for the update so it may not exist in your .acf file if you haven't prompted to update your FO4 on steam. I found these solutions after comparing the .acf files of my up to date games with my pending update FO4 one. Just throwing attempts to see what sticks.

I had success in changing the status from "Update Required" to "Play" in steam by deleting the line "DlcDownloads" including it's contents inside the brackets and also changed the "StageFlags" from 6 to 4 inside the .acf file. Then hard restarted the steam app(right-click->exit on steam icon in system tray then oper the app again).