The mismatch between the ability to explicitly rank n candidates and the presence of m > n+1 candidates on the ranking ballot is a problem that was very obvious on the NYC ballot.

There's also a practical cognitive limit - it's hard to rank more than a handful of options. Even if one allowed voters to rank 13 candidates, not many would do so.

This is one of the things I like about the Alaskan variation, where the RCV stage is capped to four voters - it has the potential for misfires, but at least it's not pushing past the capabilities of the system.