Literally who cares. Just don't buy orbs if you want to play it the normal way. Simple. No one is forcing you to buy orbs.
This isn't the same as live service games where they constantly milk DLC after the game comes out so stop pretending like it is.
"just don't buy Fortnite skins, noone is forcing you to buy Fortnite skins!"
DMC5 uses mobile game manipulation tactics like daily log-in bonuses, in-game currency abstraction to buy different in-game currencies with the in-game currency you bought with real money.
this is literally the mobile game playbook, they simply toned it down a bit.
daily log-in = fomo mechanic
buying golden orbs with red orb that are purchasable with real money = currency abstraction
Literally the 2 most use mobile game manipulation tactics aside from loot boxes