Since the mechanics for Frontier Clinics have been changed from giving habitability to reducing growth time, there's no reason for them to be disallowed on any specific planets anymore.
Upvote
0
You can still build them when you have 100% habitability from other factors, meaning that planets that have a base 100% habitability will have slower growth.Habitability now affects growth time. So since the Frontier Clinic is ment to counteract the growth time penalty from low habitability it can't be build on perfect worlds.