I see the tree structure, and I like it. I just don't know how the economic incentives might corrupt things.

Some substacker names would be inherently more valuable because they lend themselves better to generating subs-subs, like 'politics' and 'technology', and that could create some perverse incentives or just riddle the community with confusion, kind of like what's happened with reddit with legit forks from subs like 'worldnews' name themselves 'anime_titties'.