Visual Voicemail support has been integrated into Android for a couple years now. It's very noticeable on the Pixel phones as they specifically post a message in the phone app saying "Can't activate visual voicemail". I've read some forum posts that suggest activating the "visual voicemail for iPhone" add-on will actually work on the Pixel, but we should see official support from Koodo for this feature.
On the topic, this feels like a feature that should be free, and advertised as such. Nickel-and-diming customers for tiny features like this feels slimy, especially when it feels like more a feature of the phone and less a network feature. Also a good way to stand apart from the other carriers.