Is it TRULY offline-playable?

[Outsider]

I see in posts and reviews that you need to log-in before even accessing supposedly offline modes like arcade and training.
Is this true? Is this not really offline game at all?

[Toxi The Vagrant]

It has an offline mode it'll toggle to if it can't connect to the server, if this happens mid-match or while you're in a menu, you'll hard drop inputs for between 5 and 20 seconds while the toggle is happening. If it's in offline mode and you touch the multiplayer menu, you risk a softlock. By default it will try to be online unless it can't.

[OkamiB87]

I tried offline mode on steam deck and it immediately crashed the game we, need a patch for that issue asap.