3 official rulings from Bandai, last ruled Mar 28, 2024. Straight answers to how this card actually resolves.

If my opponent has 7 or more Digimon in play, does this card’s effect get reduced to negative 1, effectively gaining me a memory for using it?
No. It just reduces the cost of the card to 0. Note that in general, costs can’t be reduced to less than 0.
Ruled Mar 28, 2024
I use this card, then attack my opponent. During the security check, I flip over a Digimon card with the effect, “<Security> At the end of the battle, play this card without paying its memory cost.” What happens to this Security Digimon?
After the battle between the attacking Digimon and Security Digimon, the effect prevents the Digimon from being played, so it's placed in the trash.
Ruled Mar 28, 2024
My opponent used this card on my [BT7-063]/[DarkKnightmon]. [DarkKnightmon]'s <All Turns> effect is a "when this Digimon would be deleted" effect that interrupts deletion when it activates, but can I use this card's "your opponent can't play Digimon by effects until the end of their turn" effect to prevent [SkullKnightmon] and [DeadlyAxemon] from being played from [DarkKnightmon]'s digivolution cards?
Yes, they can't be played. This card's <Main Timing> effect was changed to "Your opponent can't play Digimon by effects until the end of their turn. Delete all of your opponent's Digimon with 6000 DP or less." Therefore, first the effect that prevents playing Digimon is applied, then Digimon with 6000 DP or less are deleted. Please see the notices regarding changes to the rules/rulings on the official website.
Ruled Mar 28, 2024
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