When you base your design upon the design of somebody else, most of the public licences require to mention the original author. The only way to do that in Tinkercad is via the comment section. Howeverit should not be to difficultto automate this:
The design description page could contain a line like:
"based upon/further development of/is a mutation of <orignal_desing> (link) by <original_designer> (link)."
At the same time the the page of the original design could contain a line:
This design was used by <secondary_designer> to build <derivative_design>.
Besides being fair it also helps users to find related designs, track design mutations and it gives a bit of status to the original designer, which stimulates people to make designs that can be useful to others.