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

What do this card's "if your opponent has 4 or less memory" and "if they have 4 or more" mean, exactly?
It means that the condition for "if your opponent has 4 or less memory" is fulfilled when the memory is at 1 through 10 on your side, 0, or 1 through 4 on your opponent's side at the timing when this effect activates. Similarly, the condition for "if they have 4 or more" is fulfilled when the memory is at 4 through 10 on your opponent's side at the timing when this effect activates.
Ruled Mar 28, 2024
If my opponent has 4 memory when this effect activates, do both the effect where 1 of my opponent's Digimon with 8000 DP or more can't attack until the end of their turn and the effect where I delete 1 of their Digimon with 6000 DP or less activate?
Yes, that's correct.
Ruled Mar 28, 2024
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