On windows, you can choose the card pool and the banlist seperately on the official servers. I do not know, if this is different for the mobile versions, but many TCG players like to test the new OCG stuff ahead of time, so allowing a format with TCG banlist and TCG+OCG cardpool makes sense. It might produce decks, that are not legal for quite some time, or might even never be playable in an official format, if a newer banlist affects them. So it is kind of a fictional format, but it does give you an idea, how a deck, that received new OCG support might play out in the current TCG format. Which might be useful information, or just a fun experience.
Now, I understand, that there are also people, who are very serious about decks being legal according to the current real-life format, so I agree with you, that this format should be at least an option. If the seperate selections for banlist and cardpool do not exist on android, they should probably be added, in my opinion.
Edited by user
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