Why Battle.net connection is « mandatory » even if we want to play offline?

Hello,

I am playing on Switch and i still love this game.
By the way, i am playing only offline mode but at the title screen there is a battle net connection mandatory if not in plane mode.

Why there is this battle net connection if we want to play offline ? I manage to change all the time my wifi to plane mode to bypass this check and it’s not fun at all.

In LoD, there is a basic menu to go to battle net and then the connection is done or playing offline without any check.

Maybe there is a part of the solution to solve the server issue here ?
Manage to use battle net only for players that want to online and not ALL the players even if there want to play offline ?

Also during this battle net connection the fan blow a lot, maybe something can be done here if there is no menu changes ?

Thanks for reading.

It’s only mandatory when you register the product after that when you put the game in off-line mode just disconnect your system from the Internet and you can play off-line forever

Yes that’s what i am doing but it’s not a feature (plane mode).
Access offline mode on title screen without connection exactly like LoD already did 20 years ago should also be present on this version.

It will also solve a little the servers issues for online players and reduce massivly the queued.