Hooking up more than 32 PCA9685s
You're right, should be 64. However, reading the datasheet:

There are a maximum of 64 possible programmable addresses using the 6 hardware address pins.

It's 6, not 5!

Two of these addresses, Software Reset and LED All Call, cannot be used
because their default power-up state is ON, leaving a maximum of 62 addresses.

Hint: always refer to the official datasheet of the device used, instead of guides built upon it, if confused about the properties of some device. There's only one official source: the datasheet.
An I²C with 62 devices might already be pretty heavily loaded. So, adding more is probably not a good idea, anyways, even if you could have more addresses.
I²C bus muxes solve the addressing problem: you have a device that acts as &quot;switch&quot; between multiple sub-busses. First you address that IC, switch to the right sub-bus, then you can talk to the I²C devices on that bus.
In your use case (thanks, @Maple), you could simply extend the I²C bus by compensating the loading by using active pull-up elements, or a bus repeater IC. See the comments.
Also, I don't know your host, but many things have multiple independent I²C buses, so you can have more than one 62-controller string to begin with.
And frankly, 62 16-channel drivers: that's already 992 channels. At some point you're reaching a complexity (and cost¹) where you can't buy Adafruit modules and &quot;wire them up&quot;, cool as they are, but need to design your own board to hold your 62 PCA6985 - especially here, because the way you route the I²C lines greatly influences the loading of them.
I'd probably start by dividing that problem down to smaller problems, rather than trying to solve it all on one I²C bus.

¹ that adafruit board is ca. USD15. That's USD 15 × 62 = USD 930 for 62 devices. Are you sure your design is affordable? The IC alone, in the quantities you want, costs ca. two dollars.  Also, still pretty much the wrong device for your choice: you have vibration motors to control.

also, if this is still about the vibration motors from your last question: people asked you to specify how much current these will draw for good reason. You haven't answered that. But I can well imagine a motor drawing more than 30 mA, so you can't use it directly with this driver anyway. And you need flyback diodes...