There's a topic with an incorrect 'Correct' answer posted here - so I want to get an actual correct answer on file (Correct Answer: Visual Voicemail on PrePaid plans should not be di... - Verizon Community) - this falsely states that the reason is because Apple's visual voicemail is built-in, but Visual Voicemail is also built into Android phones in the phone app too, particularly Google made devices like the Pixel phones. It is specifically being blocked on Android phones and allowed on Apple phones? Why treat your Android and iPhone customers on prepaid differently? My only guess is because you can get it away with it with Android as a 'punishment' for not using a traditional phone plan, but Apple won't let you use their devices on prepaid unless you agree to allow it on their phones.
This is what you get on Android (Pixel) when attempting to activate Visual Voicemail in the Phone app (calling this number just gets you someone telling you that this is only available on iPhone and not Android for prepaid customers):
