Manually add a folder, depth limit

If I were to add folders that already exist on IPFS to a new IPFS file and do this every X minute. How would pinning the top level item look like? If I were to run this for a year would that mean I just have a very very very deep folder structure or is there some inherit limit to this?

I am asking because I want to do this. I would prefer to directly use the folder but otherwise I will include the IPFS hash inside a file instead. Decoupling the linking from IPFS itself.

Pinning would mean fetching and storing the full DAG (folder tree), regardless of how deep it is. There are no inherent limits.

So it is probably better to not do this then? As it would likely create humongous trees.