Why can't we choose to play and not apply an update?

Fyi. You only need to go offline on Origin or turn off your wifi as you log into Origin and keep the page as offline. Once your logged in and Origin is set as "offline," you can turn your wifi back on right away and keep it on while listening to music.

Then Origin should stay offline as long as you don't set it back online by clicking a button for it. If for whatever reason you can't find your library page (sometimes if it's offline Origin won't load the library page) on Origin, just right click on the Origin tab icon and select "Sims 4" to launch the game offline and not through the Library.

But make sure you have automatic game updates turned off in your Origin setting. If your online Origin will try to force you to update but you can go offline for that and it cant force you that way (unless it goes automatically in which case there isn't anything you can do).

Edit: by "turn off wifi" I mean just disconnect from it.