This has been logged with support and confirmed as an active bug. I am adding here to give others an option to find it and hopefully express how impactful this is.
Templates shared with a public share link are creating duplicate custom fields in every list that is added within a folder that has folder level custom fields.
This issue does not occur within the same workspace via creating a new space or by using the share link.
It only occurs when sharing publicly with another account.
The custom fields inserted in the worksheet are tied to the list level custom fields which makes deleting them impossible without rebuilding the entire system manually for each person.
This breaks templates to the point of being 100% unusable and is holding up all of our students who are half way through onboarding to Clickup.
I know there are a billion little bugs on this list but please, fix templates so we can give people a chance to see how awesome clickup is!