can the said blockchain analysis company trace those coins after they were mixed in Wasabi?
Wasabi coordinator doesn't know anything that isn't known by the public. A chain analysis can trace the coins as they're all connected in a single transaction; it only obfuscates the final outcome. What zkSNACKs did in the recent update, is to blacklist certain outputs from being mixed, making therefore chain analysis easier.
My friends don't want their sex toy purchases found on the blockchain by their wives
Good. Bitcoin transactions do not contain information of any purchase, so there's no need for mixing. Just go with coin selection.
or possibly seen by their employers.
What kind of employers search the blockchain for their coworkers preferences? Proper coin selection should do fine. If they don't feel confident, they should use a mixing service.