To be honest, with or without this limit, it wouldn't matter at all. Unless they can find a way to track people multi-accounting via Hardware Identification (unless they are currently using that as a way to catch people), nothing will ever stop people from making new accounts.
With new technology, new exploits and new ways slip through detection and people will just make new accounts and continuously break this specific rule. (Ex: Changing HWID, Proxies, and other unorthodox ways.)
Hell even another game called osu! has this specific rule of having only just ONE ACCOUNT to play the game and prohibits making any more accounts, but people still break that rule and some are still not even caught even with the HWID/IP/proxy detection