Quite. I find it quite uninituitive how little speed you can put into a wheel by spinning it by hand (or even using sneaky dynamo-testing tactics like holding the chuck of a power drill against the tyre), compared to riding at even a gentle pace.
Also note that without the tyre, there's not a lot of flywheel mass there to store energy.
OTOH, while it's normal for dynamo hubs to feel implausibly stiff by hand, and they can make interesting buzzing noises due to the 'cogging' effect (particularly if they vibrate a truing stand or something), they shouldn't actually be making rubbing sounds.