Counter-argument is: do you really want some team of 90% marketers and PMs throwing up a MVP/WIP codebase for some ancillary product not related to your core business on your core domain? At a minimum you'd want a thorough security review and risk assessment, and that goes against the ethos of "ship fast and pivot as needed".

Why does the TLD matter in this case? How does your security/risk posture change if you launch on myexperiment.mycompany.com vs. www.mycompanyexperiment.website that you had to go out and newly purchase? Asking because I legit don't know.

I mean, it sounds like they're already doing that, just with extra downside