Can't modify attribute type

Thank you.  So I suppose I could rename the attribute to "deleted...".  But it seems that after a period of time with mistakes and changes, there will be a long list of extra attributes that are dead but can't be cleaned up.

It's hard for me to believe that there is no way to remove obsolete and even unused custom attributes.  What am I missing?

yeh.. ugly.. we use 'zzz - deprecated - old var name' as our new label for the dead variable to get it way down on the list so most users don't see it. but it makes the lists longer.

we instituted a development org to do these tests on sandbox, save the template, and destroy the sandbox so we don't replicate mistakes into production.  but we have found some side effects we didn't anticipate either..

we had a variable based on an Enum. users hated it.. so we changed the design to be a checkbox.  they love it..
then we enabled field validation (we have field that needs a specific formatted data entry)..  but now we get errors cause the enum definition was removed and there is a variable that once used it (but is no longer valid))..

how we are gonna manage this over the lifetime of RTC is gonna be a challenge

I suppose the question was more on how to recreate the attribute with different TYPE and not on maintaining the same attribute ID. As far as I know, the fields once created won't get modified or deleted from the backed as it can introduce data integrity issues.