I don't think Nintendos digital attach rate is that high. Probably 1m topds digital imo for NA, Japan, and EU. And 500-800k ROW incuding digital.
Well, we do know the average digital attach rate for Switch 1st party releases is around 10% but it seems SSBU might have easily exceeded the mark, although I can't concretly say without proof that it does.
Now, if retail sales after it's 1st month are around 8M-9M in retail only, I'd say it wouldn't be too far-fetched to think it reached the 1M milestone at least in digital sales.
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