Will there be trap clauses in the NDA and contract to see if they carefully read every line ? Will they be left with no onboarding on day one to see how far they can go by themselves ? etc.
You're starting the relationship on the base of distrust, and they don't know you, they have no idea how far you're willing to go, and assuming the worst would be the safest option.
The equivalent here would be to ask the candidate to have some folded paper showing his name on camera for the interview, not threatening them with malware.
> it's very similar to anti-phishing training/tests
With the crucial difference that the candidate is someone external who never consented to or was informed of this activity.