He has a point, though.
A fingerprint device alone does only solve one thing and that is to make it easier and faster to access something secured compared to a secure password (at least 8 characters, upper case, lower case, special characters, etc.) and that´s what Apple wants. It´s more convenient.
If Apple wants to go nuts on security, then a fingerprint sensor alone is not the perfect solution. They need more than that.
Intel and McAfee, which was bought by Intel some months ago, are developing security solutions which will make it able to access (like a smartcard or a token, which basically are the same thing) secured areas like websites with a fingerprint which is stored in your CPU (there´s a serial identifier), so no one else can forge it. This would make tokens obsolete, at least in the case when you´re using only the same device for everything. But it´s more flexible than that.
If Apple integrates a good fingerprint scanner then it would also have a lot of possible applications. It would be a new useless feature that really adds something of worth to the iPhone. They could use a highly encrypted database to store website access with your scanned fingerprint. You would also be able to transfer that encrypted fingerprint info through iCloud, which then acts as an universal fingerprint for all your devices that have a fingerprint scanner in the future.