It’s also worth noting that there’s a multitude of ways one could take over these machines if they were determined enough. The entire principle behind this is giving people shell access for giggles. So we aren’t exactly taking about VPSs for serious business here.
While security is always important for anything online, it’s also important that security is balanced against appropriateness. Here the point is a little slice of the old days even though that does invite some risk.
Unless the admin doesn’t know how to run an email server in 2022.